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General Questions

Why do we need eclipse glasses?

Wearing eclipse glasses while viewing a solar eclipse is of paramount importance for several reasons, primarily related to the protection of one's eyesight and the unique nature of the eclipse viewing experience. Here's a detailed explanation:

1. Intense Solar Radiation: The sun emits powerful ultraviolet (UV), visible, and infrared (IR) radiation. During a solar eclipse, the moon partially or fully blocks the sun, but significant amounts of this harmful radiation can still reach the eye. Eclipse glasses are designed to filter out these harmful rays.

2. Risk of Solar Retinopathy: Looking at the sun without proper protection can lead to solar retinopathy, a condition where the retina is damaged. The retina does not have pain receptors, so damage can occur without pain, and the viewer might not realize it until later. This damage can be temporary or, in severe cases, permanent, leading to impaired vision or blindness.

3. Inadequacy of Regular Sunglasses: Regular sunglasses, even very dark ones, are not sufficient to protect your eyes during a solar eclipse. They are designed for standard sunlight conditions and do not provide the necessary level of protection against the intense and concentrated solar rays experienced during an eclipse.

4. Invisible Infrared Radiation: One of the dangers of solar radiation is that you can't see or feel infrared light. This means you could be causing serious damage to your retinas, unknowingly, as IR radiation can heat the tissues and cook cells in the retina even without visible light.

5. Increased Pupil Size: In the reduced light conditions of an eclipse, your pupils may dilate, allowing more radiation to enter the eye than usual, exacerbating the potential for damage.

6. Curiosity and Prolonged Exposure: A solar eclipse is a rare and fascinating event, which can lead to people staring at the sun for much longer than they normally would. This prolonged exposure increases the risk of eye damage.

7. Safe Viewing Experience: Eclipse glasses allow you to experience the phenomenon safely, ensuring that you can enjoy the event without risking your vision. They provide a filtered view that reduces the sun's brightness to a comfortable and safe level.

8. Certification and Standards: Eclipse glasses are often ISO certified, meaning they meet specific international safety standards for direct solar viewing. This certification ensures that the glasses adequately protect your eyes from harmful solar radiation.

9. Children's Safety: It's particularly important for children, who may be more curious and less aware of the dangers, to wear eclipse glasses. Ensuring children use proper eye protection is crucial as their eyes are more sensitive.

10. Educational Value: Using eclipse glasses can be an educational experience, teaching about the importance of eye safety and the science behind solar eclipses and solar viewing.

11. Encouraging Responsible Behavior: Promoting the use of eclipse glasses sets a precedent for responsible behavior when it comes to engaging with astronomical events, fostering a culture of safety and awareness.

12. Preventing Cumulative Damage: Even if one does not experience immediate symptoms of eye damage after viewing a solar eclipse without proper protection, there could be cumulative effects that might lead to problems later in life, such as cataracts or macular degeneration.

In summary, wearing eclipse glasses during a solar eclipse is crucial for protecting your eyes from intense and potentially harmful solar radiation, ensuring a safe and enjoyable viewing experience, and fostering an awareness and understanding of the importance of eye safety during such rare astronomical events.

How do the glasses work?

Eclipse glasses are a specialized type of eyewear designed for the safe observation of solar eclipses. They are crucial because looking directly at the sun, even during an eclipse, can cause severe eye damage or blindness. Here's an in-depth explanation of how eclipse glasses work, covering various aspects:

1. Solar Radiation and Its Dangers: The sun emits intense visible light, ultraviolet (UV) radiation, and infrared (IR) radiation. Prolonged exposure to these rays, especially during an eclipse when the sun's intensity might be underestimated, can cause "solar retinopathy," a type of eye damage.

2. Material and Construction: Eclipse glasses are typically made from a scratch-resistant, black polymer material or a reflective mylar. This material is coated with a fine layer of aluminum, silver, or stainless steel on both sides.

3. Filtering of Harmful Rays: The primary function of eclipse glasses is to filter out harmful solar radiation. They are designed to block out 99.999% of visible light, as well as UV and IR radiation. This level of filtration is necessary to reduce the sun's brightness to a safe and comfortable level for viewing.

4. Optical Density and Standards: Eclipse glasses have an optical density of 5 or greater, which is much darker than typical sunglasses. They must meet international safety standards, such as the ISO 12312-2 safety standard, to ensure they effectively protect the eyes.

5. Direct Viewing of the Sun: Unlike regular sunglasses, which are not safe for viewing the sun, eclipse glasses allow individuals to look directly at the sun without any risk of eye damage. This is particularly important during solar eclipses, where the main event is the sun being obscured.

6. Working Principle: When you wear eclipse glasses and look at the sun, the lenses' filter reduces the sun's brightness to a safe level. This allows you to see the sun as a small, orange disk, enabling the observation of solar eclipses, sunspots, and other solar phenomena.

7. Importance During Eclipses: During a solar eclipse, the moon passes between the Earth and the sun, blocking out the sun's light. However, the sun's corona, or outer atmosphere, is still visible and can be safely observed with eclipse glasses.

8. Not for Use with Optical Devices: It's important to note that eclipse glasses are meant for direct viewing of the sun with the naked eye. They should not be used in conjunction with telescopes, binoculars, or cameras, as the concentrated solar rays can damage the filters and enter the eyes.

9. One-Time or Limited Use: Many eclipse glasses are designed for limited use. They can degrade over time, especially if not stored properly. It's recommended to check for any damage, such as scratches or punctures, before each use.

10. Educational and Scientific Importance: Eclipse glasses play a crucial role in educational and scientific contexts, allowing safe observation of solar phenomena. They enable students, astronomers, and the general public to experience solar eclipses, which are significant both scientifically and culturally.

11. Cultural and Historical Significance: Solar eclipses have been observed throughout history, often with great interest and awe. Eclipse glasses provide a safe way for modern observers to continue this tradition and experience the wonder of eclipses without risking their vision.

In summary, eclipse glasses are a highly specialized form of eye protection that allows safe observation of the sun during solar eclipses. They achieve this through a combination of advanced materials and optical technology designed to filter out harmful solar radiation while providing a clear view of the sun.

How often do eclipses occur?

Solar eclipses are fascinating celestial events that occur with varying frequency, depending on several factors including the type of eclipse and the specific location on Earth from which one is observing. To thoroughly understand the frequency of solar eclipses, it's essential to delve into the mechanics of how they occur, the different types of solar eclipses, and the cycles that govern their appearances.

Mechanics of Solar Eclipses


A solar eclipse happens when the Moon moves between the Earth and the Sun, casting a shadow on Earth and, for a brief period, obscuring the Sun's light. This alignment of the Sun, Moon, and Earth can only happen at New Moon, when the Moon is in its new phase.

Types of Solar Eclipses


1. Total Solar Eclipse: This occurs when the Moon completely covers the Sun, as viewed from Earth. The area from which a total eclipse is visible is known as the path of totality, which is typically only about 100 miles wide but can span thousands of miles across the Earth's surface.

2. Partial Solar Eclipse: A partial solar eclipse happens when only a part of the Sun is obscured by the Moon. This type of eclipse is visible over a much wider area than the total eclipse but does not provide the full dramatic effect of a total eclipse.

3. Annular Solar Eclipse: When the Moon is too far from Earth to completely cover the Sun, it can cause an annular eclipse. This leaves a thin ring of the solar disc visible, creating what is often called a “ring of fire.”

4. Hybrid Eclipses: These are rare and occur when the same eclipse changes from an annular to a total solar eclipse, or vice versa, along its path.


Frequency of Solar Eclipses

The frequency of solar eclipses is influenced by the Saros cycle, an 18-year, 11-day, and 8-hour period after which eclipses repeat—or nearly repeat. The extra 8 hours means the Earth has rotated about a third of the way around, so the geographical region of visibility shifts westward with each cycle.

1. Total Solar Eclipses: These are relatively rare for any given location on Earth. On average, a total solar eclipse occurs somewhere on Earth about once every 18 months. However, for any single location, total solar eclipses happen only once every 360 to 410 years, on average.

2. Partial and Annular Eclipses: These are more common than total eclipses. There are typically two to five solar eclipses of some type every year, but not all are visible from any given location. The likelihood of witnessing a partial or annular eclipse in a particular location is higher than that of a total eclipse.

Geographic Considerations

The visibility of solar eclipses is highly dependent on one's geographic location. Some regions may experience more frequent eclipses, while others, especially near the poles, may see them less often.

Long-Term Cycles


Over centuries and millennia, the frequencies and patterns of solar eclipses change due to the slow changes in Earth's orbit and axial tilt, as well as the Moon's orbit.

Are your glasses ISO compliant?

Yes! Our glasses are ISO 12312-2 compliant. This means they have met rigorous safety testing standards and are safe to use for viewing the Sun.

Can these be used with glasses?

Our glasses are meant to be worn directly on your head. However, if you wear glasses it is possible to affix the glasses, either with tape or some other adhesive or carrier of your choosing, over your existing pair of glasses.

When is it safe to put eclipse glasses on?

When observing a solar eclipse, it's crucial to understand when it's safe to wear eclipse glasses and when they are necessary for eye protection. Here's a detailed explanation:

1. Understanding Solar Eclipses: A solar eclipse occurs when the moon moves between the Earth and the sun, partially or fully blocking the sun's light. There are three types: total, partial, and annular.

2. Risks of Direct Sun Viewing: Looking directly at the sun without proper eye protection can cause "solar retinopathy," damage to the retina that can result in blurred vision or even permanent blindness.

3. Eclipse Glasses Usage: Eclipse glasses are designed to protect your eyes from the sun's harmful rays. They are much darker than regular sunglasses and filter out more light, including harmful ultraviolet and infrared rays.

4. Before Totality (Total Eclipse): If you are in the path of a total solar eclipse, you must wear eclipse glasses during the partial phases of the eclipse. This is when the moon is gradually covering the sun. The sun's rays are still harmful during these phases.

5. During Totality (Total Eclipse): The only time it is safe to look at the eclipse without glasses is during the brief phase of totality, when the sun is completely covered by the moon. This is when you can see the sun's corona, the outer atmosphere, which is safe to look at with the naked eye. However, this phase lasts only a few minutes and occurs only during a total solar eclipse.

6. After Totality (Total Eclipse): As soon as the sun begins to reappear, even slightly, it's crucial to put the eclipse glasses back on immediately to protect your eyes from the intense sunlight.

7. Partial and Annular Eclipses: If you are observing a partial or annular eclipse, where the sun is never completely covered by the moon, you must wear eclipse glasses at all times while looking at the sun.

8. Using Certified Eclipse Glasses: Ensure your eclipse glasses meet the international safety standard ISO 12312-2. Do not use regular sunglasses, smoked glass, X-ray film, or any homemade filters, as they do not provide adequate eye protection.

9. Inspecting Eclipse Glasses: Before using eclipse glasses, inspect them for any damage, such as scratches or tears. If they are damaged, they should not be used.

10. Supervising Children: Extra care should be taken when children are viewing an eclipse. Ensure they keep their eclipse glasses on at all times, except during totality in a total eclipse.

11. Photographing the Eclipse: If you plan to photograph the eclipse, your camera also needs a special solar filter to prevent damage. Do not look at the sun through an unfiltered camera, telescope, binoculars, or other optical devices.

12. After the Eclipse: If you experience discomfort or vision problems following the eclipse, seek immediate eye care from a professional.

In summary, the safety of your eyes during a solar eclipse is paramount. Eclipse glasses should be worn at all times during partial and annular eclipses, and during the partial phases of a total eclipse. The only exception is during the brief totality of a total eclipse, when the sun is completely covered by the moon.

Do your eclipse glasses protect from UV?

Our eclipse glasses are a specialized type of eyewear designed specifically for safely viewing solar eclipses. They offer critical protection against the harmful effects of the sun's rays, including ultraviolet (UV) radiation. To understand how they work, it's important to delve into several aspects:

1. Understanding UV Radiation: Ultraviolet radiation is a form of electromagnetic radiation that comes from the sun. It's not visible to the human eye but can cause significant damage to the skin and eyes. Prolonged exposure to UV rays can lead to conditions like photokeratitis (sunburn of the cornea) and cataracts.

2. The Danger of Solar Eclipses: During a solar eclipse, the moon passes between the Earth and the sun, partially or completely blocking the sun's light. The unusual darkness can cause the pupils of the eyes to dilate, allowing more light and harmful UV radiation to enter the eye, increasing the risk of eye damage.

3. Material and Construction of Eclipse Glasses: Eclipse glasses are made from a material that is capable of filtering out the harmful rays of the sun. This material is usually a polymer or a reflective coated Mylar that is specifically designed to filter out UV rays, as well as infrared radiation and intense visible light. The glasses are designed to block out 99.999% of sunlight.

4. ISO Certification and Safety Standards: To ensure safety, eclipse glasses must meet specific international safety standards. The ISO (International Organization for Standardization) 12312-2 standard is a common benchmark. Glasses that meet this standard are guaranteed to block out the necessary amount of solar radiation.

5. Filtering Out Harmful Rays: The primary function of eclipse glasses is to filter out the harmful UV rays. By doing so, they prevent these rays from reaching the retina, where they can cause damage. The glasses also reduce the sun's brightness to a safe and comfortable level, allowing the viewer to look at the sun directly without experiencing discomfort or risking injury.

6. Importance of Proper Usage: It's crucial to use eclipse glasses correctly. They should be worn whenever looking directly at the sun, especially during a solar eclipse. Even a brief glimpse of the sun's rays without protection can cause eye damage.

7. Not a Substitute for Regular Sunglasses: Regular sunglasses, even very dark ones, are not a substitute for eclipse glasses. Sunglasses are not made to protect the eyes from the intense light and radiation that comes from looking directly at the sun.

8. Educational and Preventive Role: Eclipse glasses play an important educational role by allowing people to safely observe solar phenomena. They also serve a preventive health role by protecting eyes from harmful radiation that can lead to serious and permanent eye damage.

In summary, eclipse glasses are a critical tool for safely observing solar eclipses. They are specifically designed to filter out harmful UV radiation, as well as intense visible light and infrared radiation. By doing so, they protect the eyes from potential damage while allowing individuals to experience the wonder of a solar eclipse safely.

Can children wear eclipse glasses?

Absolutely, children should use eclipse glasses during an eclipse, and it's crucial to understand why this is so important. An eclipse, whether it's a solar or lunar eclipse, presents a rare and exciting opportunity for children and adults alike to witness a spectacular natural phenomenon. However, it's essential to approach this event with safety in mind, especially for children.

Firstly, let's talk about solar eclipses, which are particularly relevant when discussing eclipse glasses. A solar eclipse occurs when the moon moves between the Earth and the Sun, partially or completely blocking the Sun's light in some areas. This event can be awe-inspiring, but it also poses significant risks to our eyes.

The sun emits powerful ultraviolet (UV) rays that can cause severe damage to the retina, the part of the eye responsible for vision. During a solar eclipse, the diminished sunlight might give the false impression that it's safe to look directly at the sun, but this is not the case. The sun's rays are still strong enough to cause retinal burns, known as solar retinopathy. This damage can be temporary or, in severe cases, permanent, leading to loss of vision.

This is where eclipse glasses come into play. Eclipse glasses are specially designed to protect eyes from the harmful effects of the sun's rays during an eclipse. They are made with solar filters that block out the vast majority of the sunlight, allowing individuals to safely observe the eclipse without risking eye damage.

For children, using eclipse glasses is even more critical. Children are naturally curious and might not understand the dangers of looking directly at the sun. Their eyes are also more sensitive, and the damage caused by the sun's rays can be more severe. Therefore, it's vital to ensure that any child watching a solar eclipse is equipped with a pair of certified eclipse glasses.

It's important to note that regular sunglasses, no matter how dark, are not a safe substitute for eclipse glasses. Eclipse glasses must meet specific safety standards (ISO 12312-2) to ensure they effectively protect your eyes. Always check for this certification before purchasing or using eclipse glasses.

In addition to using eclipse glasses, adult supervision is crucial when children are observing a solar eclipse. Adults can ensure that the glasses fit properly and stay on, and they can also guide children on how to safely use them. It's a good practice to teach children not to look directly at the sun without proper protection, not just during an eclipse but at all times.

In summary, the use of eclipse glasses for children during a solar eclipse is not just a recommendation; it's a necessity. These glasses provide essential protection against the harmful effects of the sun's rays, ensuring that children can enjoy the wonder of an eclipse without risking their eye health. By combining the use of certified eclipse glasses with adult supervision, we can create a safe and educational experience for children during these extraordinary celestial events.

Do you offer discounts for schools?

Yes! We offer two discounts: a general school discount that increases with the amount of pairs ordered and a Title 1 discount.

We believe it is critical for students to have the opportunity to view the upcoming April 2024 total eclipse, the last one for 99 years. As such, we are committed to providing schools with ISO certified eclipse glasses.

Please contact us at info@eclipse23.com for school pricing.

Are eclipse glasses reusable?

Eclipse glasses are indeed reusable, provided they are stored safely and remain undamaged. According to information from Eclipse Glasses USA, their solar eclipse glasses are designed to be durable and reusable. These glasses are ISO 12312-2:2015 Certified, CE Certified, AAS Approved, and NASA Approved. They are made using a silver polymer solar filter/film that effectively blocks harmful UV, visible, and IR radiation from the Sun. The frames are constructed from sturdy paperboard, suggesting a level of durability that supports multiple uses.

However, it's important to note that the reusability of eclipse glasses depends on their condition. If the lenses are scratched, punctured, torn, or otherwise damaged, they should not be used again. Additionally, if the glasses are several years old, it's advisable to check for any degradation or wear that might compromise their safety. Proper storage and careful handling are key to ensuring that eclipse glasses remain safe and effective for future solar eclipses.

What sets Eclipse Glasses USA's eclipse glasses apart from others?

1. Certification and Safety Standards: High-quality eclipse glasses, such as those from Eclipse Glasses USA, are typically CE and ISO certified. This means they meet specific safety standards for direct sun viewing, ensuring that they effectively protect your eyes from harmful solar radiation during an eclipse.

2. Manufacturing Quality: Eclipse glasses from reputable companies are often made with superior materials and manufacturing processes. This ensures durability and reliability, which are crucial for eye safety during an eclipse. Our eclipse glasses are manufactured in the USA and meet the highest ISO and CE standards.

3. Optical Density and Filtering: The best eclipse glasses have an optical density sufficient to safely view the sun. They filter out harmful ultraviolet, visible, and infrared radiation, allowing you to view the eclipse without risking eye damage.

4. Comfort and Ease of Use: Top-rated eclipse glasses are designed for comfort, with a secure fit that accommodates different face shapes and sizes. They are also easy to use, making them accessible to a wide range of users, including children and adults.

5. Educational and Informative Packaging: Many high-quality eclipse glasses come with educational material about solar eclipses, instructions for safe viewing, and information about the glasses' specifications and certifications.

6. Positive Customer Reviews: Products like Eclipse Glasses USA's often have numerous positive reviews and testimonials, indicating high customer satisfaction. These reviews can provide insights into the glasses' effectiveness, comfort, and overall quality.

7. Brand Reputation: Established brands in the field of astronomical products and eclipse glasses, such as Eclipse Glasses USA, have a reputation for quality and reliability, which is often a result of years of experience and customer trust.

8. Ownership: we are founded and owned by science educators who understand the scientific and educational value of viewing eclipses.

Does the color of the eclipse glasses' lens matter?

The color of solar filters on eclipse glasses does not directly impact their safety, but it is crucial to understand that the safety of these glasses is determined by the quality and properties of the material used in the solar filters, not by their color. Eclipse glasses are designed to protect your eyes from the intense light of the sun, including harmful ultraviolet (UV), visible, and infrared (IR) radiation, during an eclipse. The safety and effectiveness of these glasses are primarily dependent on the materials used to construct the solar filters and their compliance with established safety standards, rather than their color.

1. Material and Construction: The most critical aspect of eclipse glasses is the material used for the solar filters. These filters are usually made from a special-purpose solar viewing film that has a thin layer of aluminum deposited on the substrate. This material is designed to filter out the vast majority of sunlight, allowing only a fraction of the sun's light to pass through. This reduction in light intensity is what makes direct solar viewing safe during an eclipse.

2. Compliance with Safety Standards: Safety standards such as ISO 12312-2:2015 are crucial for eclipse glasses. These standards ensure that the glasses reduce visible sunlight to safe and comfortable levels and block harmful ultraviolet and infrared radiation. The compliance of eclipse glasses with these standards is a key factor in their safety, not the color of the filters.

3. Color Perception and Comfort: While the color of the solar filters does not affect safety, it can influence color perception and viewing comfort. Different materials and coatings can produce different colored views of the sun, typically varying from orange, yellow, to white. However, this color variation is more about the viewing experience and does not correlate with the level of eye protection provided.

4. Avoiding False Security: It's important not to equate the color of the filters with safety. Darker or a specific color does not automatically mean better protection. The effectiveness of eclipse glasses in protecting your eyes from harmful solar radiation is determined by the material's ability to filter out the appropriate wavelengths and intensities of light, not by how dark or what color the lenses appear to be.

5. Counterfeit Products: There is a risk of counterfeit eclipse glasses that may not meet safety standards, regardless of their color. It's essential to purchase eclipse glasses from reputable vendors and to verify that they meet the necessary safety standards.

6. Regular Sunglasses Insufficiency: Regular sunglasses, regardless of how dark they are, are not safe for viewing the sun. They do not provide the necessary UV and IR radiation protection required for direct solar viewing.

7. Scratches and Damages: The integrity of the solar filter is crucial. Scratches, punctures, or damages to the filter material can compromise safety. Regular inspection of the glasses for any damage is important, irrespective of their color.

8. Educational and Public Awareness: Educating the public about the importance of using proper solar viewing equipment during eclipses is vital. Emphasis should be on the material's properties and compliance with safety standards rather than the color of the filters.

In summary, the color of solar filters on eclipse glasses is not a determinant of their safety. The critical factors are the material's ability to filter out harmful solar radiation and compliance with established safety standards. When choosing eclipse glasses, one should focus on these aspects rather than the color of the lenses.

Orders, Shipping & Returns

When should I order?

Anyone who attempted to get these glasses for the 2017 eclipse may recall how difficult it became to acquire these the closer we approached the eclipse date. Don't make the same mistake again. Prices for these will increase as demand skyrockets in the 6-8 weeks leading up to the eclipse date. Order now so you don't have to worry in October.

How are orders shipped?

We offer USPS and UPS options that are selected at checkout. Please understand that once we ship an order, any issues experienced become an issue with the carrier, not Eclipse Glasses USA. We will ship according to our store policies.

Do you ship internationally?

For the April 2024 eclipse, shipping to Mexico and Canada will be our only international shipping options.

Do you accept returns?

For returns, please contact us at info@eclipse23.com

Taking Care of Your Glasses

How do I store my eclipse glasses?

Storing eclipse glasses properly is crucial to ensure they remain safe and effective for viewing future solar eclipses. Here's a detailed guide on how to store them:

1. Inspection Before Storage: Before storing your eclipse glasses, inspect them for any damage. Look for scratches, tears, punctures, or any damage to the lenses. If the glasses are damaged, they should be disposed of, as they are no longer safe for viewing eclipses.

2. Cleaning (If Necessary): If the glasses need cleaning, do it gently. Use a soft, dry cloth to lightly wipe the lenses. Avoid using water, cleaning fluids, or any abrasive materials that could scratch or damage the lenses.

3. Avoid Folding: Do not fold the glasses, especially not the lenses. Folding can create creases or damage the protective solar filter.

4. Use a Protective Sleeve or Envelope: Place the glasses in a protective sleeve or envelope. This could be the original packaging they came in, or any other light-proof sleeve that can protect them from dust and scratches.

5. Store in a Cool, Dry Place: Choose a storage location that is cool and dry. Avoid places with high humidity or extreme temperatures, as these conditions can degrade the lenses over time. A drawer, a closet, or a storage box in a temperature-controlled room is ideal.

6. Keep Away from Direct Sunlight: Do not store the glasses where they will be exposed to direct sunlight. Prolonged exposure to sunlight can degrade the protective filters.

7. Avoid Pressure: Store the glasses in a place where they won’t be crushed or bent under heavy objects. Pressure can damage the lenses and the frame, making them unsafe for future use.

8. Label the Storage Location: If you’re storing multiple pairs or storing them in a place with other items, label the storage location. This helps in easily finding them when needed and prevents them from being mistakenly used for purposes other than viewing solar eclipses.

9. Check Periodically: If you plan to store the glasses for a long time, it’s a good idea to check on them periodically. This ensures they remain in good condition and are ready for use when the next eclipse occurs.

10. Educate Others: If others in your household or organization will be accessing or using these glasses, make sure they are aware of the importance of handling and storing them properly.

11. Consider Expiry: Be aware that some eclipse glasses come with a recommended shelf life (often around 3 years). Check the manufacturer's recommendations and be cautious of using glasses past their suggested expiry date.

12. Disposal if Necessary: If you find that the glasses are no longer usable, dispose of them properly. Do not use them for viewing the sun, as damaged filters can lead to serious eye injury.

By following these detailed steps, you can ensure that your eclipse glasses are well-maintained and safe for use during future solar eclipses. Remember, the safety of your eyes during an eclipse depends significantly on the condition of the eclipse glasses you use.

How do I clean my eclipse glasses?

Cleaning eclipse glasses is a delicate process that requires careful handling to ensure they remain effective and safe for viewing solar eclipses. Here's a detailed, step-by-step guide on how to clean your eclipse glasses:

1. Understand the Material: Eclipse glasses are typically made with a special solar filter film that is very sensitive. It's important to know that this material can be easily scratched or damaged, which would make the glasses unsafe for future use.

2. Inspect the Glasses First: Before cleaning, inspect your eclipse glasses for any damage, such as scratches, tears, or punctures. If the lenses are damaged, do not use them again. Damaged eclipse glasses can allow harmful solar radiation to pass through and damage your eyes.

3. Gather Gentle Cleaning Materials: You will need a soft, lint-free cloth (like those used for cleaning eyeglasses or camera lenses), and a source of clean, running water. Avoid using any harsh cleaning chemicals, abrasives, or rough materials like paper towels, as these can scratch the film.

4. Rinse with Water: If there is any loose dust or debris on the glasses, gently rinse them under a stream of lukewarm water. This step helps to prevent scratching the lenses when you wipe them. Do not use hot water, as it might damage the film.

5. Apply a Mild Soap (If Necessary): For smudges or fingerprints, you can use a tiny drop of mild, non-moisturizing soap. Avoid using strong detergents or soaps with added scents, lotions, or other additives.

6. Gently Wipe the Lenses: Using the soft cloth, gently wipe the lenses in a circular motion. Be very gentle to avoid scratching. If you used soap, ensure you rinse all of it off with lukewarm water.

7. Air Dry or Dab Gently: After cleaning, let the glasses air dry or gently dab them with a dry part of the lint-free cloth. Do not rub the lenses to dry them as this could cause scratches.

8. Store Properly: Once the glasses are dry, store them in a protective sleeve or envelope, away from direct sunlight and heat. This helps to keep them clean and prevents any damage to the lenses.

9. Regular Checks: Regularly check your eclipse glasses for any damage before and after cleaning. Remember that these glasses are meant for specific use and should be maintained with care.

10. Avoid Unnecessary Cleaning: Clean your eclipse glasses only when necessary. Frequent cleaning can increase the risk of scratching or damaging the delicate film.

11. Consult Manufacturer's Instructions: If available, refer to the cleaning instructions provided by the manufacturer of your eclipse glasses, as some may have specific recommendations or warnings.

12. Safety First: Remember, the primary purpose of eclipse glasses is to protect your eyes from harmful solar radiation. Any cleaning method that compromises the safety of the glasses should be avoided.

By following these detailed steps, you can ensure that your eclipse glasses remain in good condition and safe for use during solar eclipses. Remember, safety is paramount when viewing solar events, and taking care of your eclipse glasses is a key part of that safety.

How do I extend the life of my eclipse glasses?

Extending the longevity of eclipse glasses is important for ensuring they remain safe and effective for viewing solar eclipses. Here are detailed steps and considerations to maximize their lifespan:

1. Understand the Material and Construction: Eclipse glasses are typically made from a special solar viewing material that filters out harmful solar radiation. Knowing the material helps in understanding how to care for them.

2. Proper Storage: Store the glasses in a cool, dry place. Avoid areas with high humidity or extreme temperatures, as these conditions can degrade the protective filters.

3. Use a Protective Case: To prevent scratches and physical damage, store the glasses in a rigid or semi-rigid protective case. This is especially important for glasses with plastic lenses.

4. Avoid Folding and Bending: Repeatedly folding or bending the glasses, especially those made of cardboard, can weaken their structure and potentially damage the solar filter.

5. Handle with Care: When using the glasses, handle them gently. Avoid touching the lenses with your fingers, as oils and dirt from your skin can damage the solar filter.

6. Clean Gently: If the glasses need cleaning, use a soft, lint-free cloth. Avoid using water, cleaning fluids, or any abrasive materials, as these can scratch or remove the protective coating.

7. Check for Damage Regularly: Before each use, inspect your eclipse glasses for any scratches, punctures, tears, or damage to the lenses. If any damage is found, the glasses should be discarded as they may no longer be safe for viewing the sun.

8. Limit Exposure to Light and Air: When not in use, keep the glasses in a dark place where they are not exposed to light or air, which can degrade the materials over time.

9. Avoid Extreme Pressure: Don’t place heavy objects on top of the glasses, and avoid situations where they might get crushed or bent.

10. Educate Others: If you lend your glasses to others, make sure they know how to handle and care for them properly.

11. Follow Manufacturer Guidelines: Pay attention to any specific care instructions provided by the manufacturer. Some glasses may have a limited lifespan and need to be replaced after a certain period, regardless of their physical condition.

12. Consider Upgrades: If you plan to view eclipses regularly, consider investing in more durable, professional-grade solar viewing glasses.

13. Stay Informed: Keep up-to-date with information from astronomical organizations about the safety and efficacy of eclipse glasses, as standards and recommendations can evolve.

14. Plan for Replacement: Even with the best care, eclipse glasses may eventually need to be replaced. Plan ahead for this, especially if an eclipse is approaching.

15. Recycle or Dispose Properly: If your glasses are no longer usable, dispose of them properly. Some components might be recyclable.

16. Educational Use: If the glasses are no longer suitable for eclipse viewing, consider using them for educational purposes, like demonstrating how solar filters work.

17. Backup Pair: It’s always a good idea to have a backup pair of eclipse glasses, just in case your primary pair gets damaged.

By following these detailed steps, you can significantly extend the life of your eclipse glasses, ensuring they remain safe and effective for solar viewing for as long as possible.

What do I do if my eclipse glasses get damaged?

If your eclipse glasses are damaged, it's crucial to understand the risks and necessary precautions for viewing a solar eclipse safely. Here's a detailed explanation:

1. Understanding the Risks: The sun emits intense light and ultraviolet radiation. Looking at the sun without proper protection, even during an eclipse, can cause "eclipse blindness" or retinal burns, known as solar retinopathy. This damage can be temporary or permanent and occurs without pain, as the retina does not have pain receptors.

2. Recognizing Damage in Eclipse Glasses: Inspect your eclipse glasses before every use. Look for scratches, punctures, tears, or any damage to the lenses. If the glasses are wrinkled, torn, or if the lenses are coming loose from the frame, they are not safe to use. Even a small amount of damage can significantly reduce the effectiveness of the glasses.

3. Do Not Use Damaged Eclipse Glasses: If you find any damage, do not use the glasses. Using damaged eclipse glasses can result in severe eye injury. The protective filters in eclipse glasses are designed to block out the majority of the sun's light, and any compromise to this filter can allow harmful rays to pass through.

4. Alternative Viewing Methods: If your eclipse glasses are damaged and you cannot replace them, consider alternative methods to view the eclipse safely:
- Pinhole Projector: This is a simple and safe way to view the eclipse. You can make one using two pieces of cardstock or paper. Make a small hole in one piece of paper using a pin, and let the sunlight fall through that hole onto the second piece of paper, which works as a screen.
- Viewing Parties: Many local organizations, like planetariums, science museums, and astronomy clubs, often host eclipse viewing events with proper solar viewing equipment.
- Live Streams: Numerous websites and TV channels broadcast live streams of eclipses, allowing you to experience the event without any risk to your eyes.

5. Purchasing New Eclipse Glasses: If you have time before the eclipse, you can purchase new eclipse glasses. Make sure they meet the international standard ISO 12312-2 for safe viewing.

6. Educating Others: Share this information with friends and family who plan to view the eclipse. Many people are unaware of the risks of using damaged eclipse glasses.

7. Disposing of Damaged Glasses: Properly dispose of any damaged eclipse glasses to prevent them from being inadvertently used.

8. Plan Ahead for Future Eclipses: If you're interested in viewing future solar eclipses, plan ahead and purchase certified eclipse glasses well in advance. This ensures you have the proper equipment when the time comes.

9. Consulting Eye Care Professionals: If you have viewed an eclipse using damaged glasses and are experiencing any discomfort or vision problems, consult an eye care professional immediately.

10. Staying Informed: Keep yourself informed about the best practices for eclipse viewing. Organizations like NASA, the American Astronomical Society, and local astronomy clubs often provide valuable information and resources.

In summary, never take risks when it comes to viewing a solar eclipse. The safety of your eyes is paramount, and there are several safe and enjoyable ways to experience this spectacular astronomical event without compromising your eye health.

How do I dispose of my eclipse glasses?

Disposing of used or damaged eclipse glasses requires careful consideration to ensure environmental safety and proper recycling. Eclipse glasses are primarily designed for single-use and are made from a variety of materials, including paper, plastic, and a special solar filter film. Here's a detailed guide on how to dispose of them properly:

1. Understand the Materials: Eclipse glasses typically consist of a cardboard or paper frame and a special solar filter. The filter is a crucial component, made from black polymer or other materials capable of protecting eyes from harmful solar radiation.

2. Assess the Condition: If the glasses are undamaged and meet the ISO 12312-2 safety standard, they may be reusable for future solar eclipses. Check the manufacturer's instructions for the lifespan and storage conditions.

3. Recycling the Frame: If the frame is made of cardboard or paper, it can often be recycled with other paper products. However, it's important to remove any plastic or non-paper components attached to the frame, such as earpieces or lenses, as these parts may not be recyclable through standard municipal recycling programs.

4. Disposing of the Solar Filter: The solar filter is the most critical part to dispose of correctly. This filter, if not damaged, can be reused. However, if it's scratched, punctured, or otherwise compromised, it should not be used again. Unfortunately, the solar filter material is not typically recyclable due to its specialized nature. Therefore, it should be disposed of in the trash unless the manufacturer provides a specific recycling program.

5. Consider Upcycling: Before disposing of the glasses, consider if they can be repurposed or upcycled. For example, the frames can be used for crafts or educational projects, especially in schools or community centers.

6. Check with Local Waste Management: Some local recycling programs may have specific guidelines or programs for recycling eclipse glasses. It's worth checking with them to see if they offer a specialized recycling option.

7. Manufacturer Take-Back Programs: Some manufacturers of eclipse glasses offer take-back programs where you can send back your used glasses for proper disposal or recycling. Check the manufacturer's website for such programs.

8. Educational Donations: If the glasses are still in good condition, consider donating them to schools, libraries, or educational organizations that might store them safely for use in future eclipses.

9. Avoid Littering: Never litter used eclipse glasses. Improper disposal can harm the environment and wildlife.

10. Spread Awareness: Educate others about the importance of proper disposal of eclipse glasses. Sharing information can help ensure more glasses are disposed of responsibly.

11. Environmental Considerations: Remember that proper disposal is not just about getting rid of the glasses but doing so in a way that minimizes environmental impact. Consider the entire lifecycle of the product, from production to disposal.

12. Legal Compliance: Ensure that your method of disposal complies with any local, state, or national environmental regulations.

13. Safety First: If you're unsure about the safety of your eclipse glasses for future use, it's better to dispose of them than risk eye damage.

14. Online Resources: Utilize online resources for more information on recycling programs and creative ideas for repurposing eclipse glasses.

15. Community Involvement: Engage with community programs or events focused on recycling and proper disposal of such materials.

By following these detailed steps, you can ensure that your used or damaged eclipse glasses are disposed of in a responsible, environmentally friendly manner.

How long do eclipse glasses last?

Eclipse glasses are a specialized type of eyewear designed specifically for safely viewing solar eclipses. Their primary function is to protect the eyes from harmful solar radiation during an eclipse, a time when people are tempted to look directly at the sun. Understanding the lifespan and durability of eclipse glasses involves considering several factors, including the materials used, the storage conditions, and the standards they adhere to.

1. Material Composition: Eclipse glasses are typically made from a scratch-resistant, black polymer material or a silver-black polymer that is extremely dense, infused with a fine layer of aluminum to filter out the harmful solar rays. This material is designed to block out 99.999% of intense visible light and 100% of harmful ultraviolet and infrared rays.

2. ISO Certification and Safety Standards: Reputable eclipse glasses adhere to a high standard of safety, often certified by the International Organization for Standardization (ISO). ISO 12312-2 is a specific standard for eclipse glasses that ensures they are safe for direct solar viewing. Glasses meeting these standards are guaranteed to have the necessary optical density and are free from defects that would compromise safety.

3. Degradation Over Time: The protective filters in eclipse glasses can degrade over time. Factors such as exposure to moisture, scratches on the lenses, or general wear and tear can diminish their effectiveness. While there is no strict "expiration date," manufacturers often recommend that, if properly cared for and stored, eclipse glasses can be used for a few years after their production date.

4. Proper Storage: To extend the lifespan of eclipse glasses, they should be stored in a cool, dry place. They should be kept away from direct sunlight, heat sources, and any environment where they might get scratched or bent. Keeping them in a protective sleeve or envelope is ideal.

5. Visual Inspection Before Use: Before using eclipse glasses, especially if they have been stored for a long time, it is crucial to inspect them for any damage. Look for scratches, punctures, tears, or any light leaks. If the glasses are damaged in any way, they should not be used, as even a small defect can allow harmful solar radiation to pass through.

6. Manufacturer's Recommendations: Always refer to the manufacturer's guidelines regarding the lifespan and use of their eclipse glasses. Different brands may have different recommendations based on the materials and technology they use. Our manufacturer recommends discarding your eclipse glasses after three years.

7. Safe Viewing Practices: It's important to remember that eclipse glasses are meant for intermittent viewing of the sun, not continuous observation. They should be put on while looking away from the sun, and then it's safe to look at the sun. One should look away from the sun before removing them.

8. Alternatives for Long-Term Use: For those interested in regularly observing the sun, such as amateur astronomers, investing in more durable, long-term solar viewing equipment like solar telescopes or welder's glasses rated at 14 or higher might be more appropriate.

9. Disposal and Recycling: If eclipse glasses are no longer safe to use, they should be disposed of properly. Some components might be recyclable, depending on the materials used.

In summary, while eclipse glasses don't have a fixed expiration date, their lifespan can be several years if they are stored properly and kept in good condition. However, it is crucial to inspect them before each use to ensure they provide adequate protection, and to adhere to the manufacturer's guidelines and safety standards. For frequent solar observers, more permanent solutions might be more appropriate.

Certifications & Endorsements

Are your eclipse glasses ISO certified?

Yes! Our eclipse glasses are indeed certified by ISO and meet the 12312-2:2015 safety standards as set forth by ISO. You can read more here about what this means.

Are your eclipse glasses CE certified?

Yes! Our manufacturer produces Eclipse Glasses USA's eclipse glasses in a facility that can meet CE standards. As a result, they have gained CE certification for our eclipse glasses.

Are you an American Astronomical Society (AAS) approved vendor?

Yes! We get this question often. We are indeed listed on the AAS website under "resellers". Our glasses are made in the USA and our company is headquartered and charted in Utah. When you buy from Eclipse Glasses USA, you buy American and that means our glasses meet the highest safety standards on the market. For more information, see here.

School Discounts

Do you offer special pricing for schools?

Yes! Eclipse Glasses USA has launched a comprehensive Educator Discount Program designed specifically for schools, ensuring that students can safely experience the wonder of solar eclipses. This program is particularly notable for its inclusivity, catering to various types of educational institutions:

Non-Title 1 Schools: These schools are eligible for a standard discount on solar eclipse glasses. The glasses provided are of high quality, being ISO 12312-2:2015 Certified, CE Certified, AAS Approved, and NASA Approved. This certification guarantees that the glasses meet the highest safety standards, effectively blocking harmful UV, visible, and IR radiation from the sun. The glasses are designed, made, and shipped within the USA, using a silver polymer solar filter.

The program underscores Eclipse Glasses USA's commitment to educational equity and the safe enjoyment of solar eclipses. It's not merely a discount scheme but a dedication to facilitating an awe-inspiring educational experience for all students, regardless of their school's financial situation.

For more detailed information or to participate in the program, schools can reach out to Eclipse Glasses USA at info@eclipse23.com. It's advisable to act promptly, especially with the upcoming April eclipse.

Do you offer special pricing for Title 1 schools?

Yes!

Eclipse Glasses USA has launched a comprehensive Educator Discount Program designed specifically for schools, ensuring that students can safely experience the wonder of solar eclipses. This program is particularly notable for its inclusivity, catering to various types of educational institutions.

Recognizing the budget constraints often faced by Title 1 schools, Eclipse Glasses USA offers these institutions the glasses at cost. This initiative is a significant step towards ensuring that financial limitations do not impede the educational experiences of students in these schools. It allows them to access high-quality, reliable eclipse glasses affordably.

The program underscores Eclipse Glasses USA's commitment to educational equity and the safe enjoyment of solar eclipses. It's not merely a discount scheme but a dedication to facilitating an awe-inspiring educational experience for all students, regardless of their school's financial situation.

For more detailed information or to participate in the program, schools can reach out to Eclipse Glasses USA at info@eclipse23.com. It's advisable to act promptly, especially with the upcoming April eclipse.

Do you offer special pricing for special needs schools?

Yes!

In an effort to include all student populations, Eclipse Glasses USA extends its program to schools serving special needs populations by donating glasses. This gesture ensures that these students are not excluded and can safely partake in observing solar eclipses.

The program underscores Eclipse Glasses USA's commitment to educational equity and the safe enjoyment of solar eclipses. It's not merely a discount scheme but a dedication to facilitating an awe-inspiring educational experience for all students, regardless of their school's financial situation.

For more detailed information or to participate in the program, schools can reach out to Eclipse Glasses USA at info@eclipse23.com. It's advisable to act promptly, especially with the upcoming April eclipse.

Corporate Discounts

Do you offer discounts for businesses/corporations?

Yes!

Eclipse Glasses USA offers an exclusive corporate discounts program for businesses interested in purchasing ISO-certified solar eclipse glasses in bulk. This program is designed to make solar eclipses more accessible and safer for everyone, including businesses of all sizes. Here are some key aspects of our program and the benefits of viewing an eclipse with coworkers:

Corporate Bulk Discounts on Solar Eclipse Glasses


- Exclusive Discounts: Eclipse Glasses USA provides special discounts for corporate bulk orders. This can include company-wide events, client outreach programs, or unique corporate gifts.
- ISO Certified Glasses: The glasses are ISO certified, ensuring they meet international safety standards for directly viewing the sun.
- Quality and Safety: The company prioritizes safety and quality, offering top-quality eclipse glasses that guarantee a safe and enjoyable viewing experience.

Benefits of a Shared Solar Eclipse Experience with Coworkers


- Fostering Team Spirit: Viewing a solar eclipse together can create unforgettable bonding moments for team members. It's an innovative and exciting way to engage the team and foster company culture.
- Unique Corporate Event: Organizing a solar eclipse viewing event is a unique opportunity that can stand out as a memorable experience for employees.

Contacting Eclipse Glasses USA

Businesses interested in the corporate discounts program can contact Eclipse Glasses USA for a personalized quote. Our customer service team is ready to assist in planning an unforgettable solar eclipse experience for companies.

Viewing a solar eclipse with coworkers can be a great experience because it offers a rare opportunity to witness a spectacular celestial event together. It can enhance team bonding, provide a break from the usual work routine, and add an element of excitement and wonder to the workplace environment.

The Science

What is the science behind what causes solar eclipses to occur?

Solar eclipses are a fascinating celestial event where the Moon passes between the Earth and the Sun, temporarily obscuring the Sun's light. This phenomenon is a result of the intricate dance of celestial mechanics involving the Earth, the Moon, and the Sun. To understand the science behind solar eclipses, we need to delve into several aspects of astronomy, physics, and geometry.



1. Orbital Mechanics


- Earth's Orbit Around the Sun: The Earth orbits the Sun in an elliptical path, taking approximately 365.25 days to complete one revolution. This orbit is crucial in determining the position of the Earth relative to the Sun throughout the year.
- Moon's Orbit Around Earth: Similarly, the Moon orbits the Earth in an elliptical orbit, taking about 27.3 days to complete one orbit. The plane of the Moon's orbit is inclined at about 5 degrees to the plane of the Earth's orbit around the Sun, known as the ecliptic plane.


2. The Ecliptic Plane


- Understanding the Ecliptic: The ecliptic plane is the imaginary plane created by the Earth's orbit around the Sun. The apparent path of the Sun across the sky, as seen from Earth, lies in this plane.
- Inclination of the Moon's Orbit: The Moon’s orbital plane is inclined to the ecliptic, which means that the Moon often passes above or below the Sun from our vantage point on Earth. This inclination is why we do not have solar eclipses every month.


3. Types of Solar Eclipses


- Total Solar Eclipse: Occurs when the Moon completely covers the Sun, as viewed from Earth. This can only happen at new moon when the Sun and the Moon are in conjunction as seen from Earth in an alignment known as syzygy.
- Partial Solar Eclipse: When only a part of the Sun is obscured by the Moon.
- Annular Solar Eclipse: Happens when the Moon covers the Sun's center, leaving the Sun's visible outer edges to form a “ring of fire” or annulus around the Moon.


4. Syzygy and Alignment


- Alignment of Sun, Moon, and Earth: For a solar eclipse to occur, the Sun, Moon, and Earth must be nearly in a straight line. This alignment happens at new moon (when the Moon is between the Earth and the Sun).
- Variation in Distance: The varying distances of the Moon from the Earth (due to its elliptical orbit) affect the type of eclipse. When the Moon is farther away, it appears smaller and cannot completely cover the Sun, leading to an annular eclipse.


5. Shadow Play


- Umbra: The Moon's umbra is the fully shaded inner region of its shadow. In a total solar eclipse, this umbra falls on a part of the Earth.
- Penumbra: The partially shaded outer region of the shadow. A partial eclipse is seen within this region.


6. Saros Cycle


- Eclipse Predictability: Eclipses follow an 18-year cycle known as the Saros cycle, allowing astronomers to predict when and where an eclipse will occur.


7. Historical and Cultural Significance


- Historical Observations: Solar eclipses have been recorded and interpreted in various ways throughout history, influencing science, mythology, and art.


8. Scientific Research and Solar Eclipses


- Solar Corona: Solar eclipses, especially total eclipses, allow scientists to study the Sun’s corona (the outer atmosphere).
- Advancements in Astrophysics: Observations during eclipses have contributed to significant scientific discoveries, including the confirmation of Einstein’s theory of general relativity.


9. Safety in Viewing


- Eye Protection: Viewing a solar eclipse requires special protective eyewear to prevent eye damage.


10. The Role of Gravity


- Gravitational Interactions: The gravitational forces between the Earth, Moon, and Sun govern their orbits and lead to the occurrence of eclipses.


11. Angular Size and Perception


- Apparent Size Differences: The similar apparent sizes of the Moon and Sun in Earth's sky are a coincidence of their respective distances and sizes, making total solar eclipses possible.


12. Frequency and Duration


- Variability: The frequency and duration of solar eclipses vary, influenced by the orbital dynamics of the Earth and Moon.


13. Eclipse Seasons


- Eclipse Nodes: Eclipses can only occur when the Moon crosses the ecliptic at points known as nodes, which happens roughly every six months, defining the eclipse seasons.


14. Global Phenomenon


- Path of Totality: The path of totality (where a total eclipse is visible) is a narrow track across the Earth's surface.


15. Astrophotography and Eclipses


- Documenting Eclipses: Eclipses provide unique opportunities for astrophotography, contributing to both science and art.

In summary, solar eclipses are a result of the complex and precise alignment of the Earth, Moon, and Sun. The science behind them encompasses a range of disciplines, including orbital mechanics, geometry, physics, and astronomy. These events not only offer a spectacular view but also provide valuable opportunities for scientific research and have a rich history in human culture and understanding of our universe.

Why do eclipses follow a specific path?

Solar eclipses are fascinating celestial events that occur when the Moon passes between the Earth and the Sun, temporarily obscuring the Sun's light. The path taken by a solar eclipse, often referred to as the path of totality, is determined by a complex interplay of celestial mechanics involving the orbits of the Earth and the Moon, as well as their relative positions to the Sun. To understand why solar eclipses take the paths they do, we need to delve into several aspects of astronomy and celestial dynamics.


1. Orbital Mechanics


- Earth's Orbit Around the Sun: The Earth orbits the Sun in an elliptical path, which means its distance from the Sun varies throughout the year. This orbit is not perfectly circular but slightly elongated.

- Moon's Orbit Around Earth: Similarly, the Moon orbits the Earth in an elliptical orbit. The plane of the Moon's orbit is not exactly aligned with the plane of the Earth's orbit around the Sun (the ecliptic plane). Instead, it is inclined at an angle of about 5 degrees.


2. Alignment of Sun, Moon, and Earth


- Syzygy: For a solar eclipse to occur, the Sun, Moon, and Earth must be nearly in a straight line, a configuration known as syzygy. This alignment happens during a new moon phase when the Moon is between the Earth and the Sun.

- Ecliptic Intersection: The points where the Moon's orbit intersects the Earth's orbital plane are called nodes. A solar eclipse can only occur if the new moon happens near one of these nodes.


3. Variation in Eclipse Paths


- Orbital Inclination: Because of the 5-degree tilt of the Moon's orbit relative to the Earth's orbit, the shadow of the Moon (which causes the eclipse) does not always fall on the Earth. It usually passes either above or below our planet.

- Changing Distances: The varying distances of the Moon from the Earth and the Earth from the Sun also affect the eclipse's path. When the Moon is closer to Earth, it can completely cover the Sun (total eclipse); when it's farther, it might not cover the Sun completely (annular eclipse).

- Earth's Rotation: The rotation of the Earth on its axis also plays a role. As the Earth rotates, the location of the Moon's shadow moves across the Earth's surface, tracing a path that we observe as the path of the eclipse.

- Precession of Orbits: The orbits of the Earth and the Moon are not static. They precess or wobble over time, which means the conditions for an eclipse (the alignment of the nodes with the new moon) shift over years.


4. Predicting Eclipse Paths


- Saros Cycle: Eclipses tend to recur in cycles known as Saros cycles, approximately every 18 years. However, each recurrence sees the path of totality shifted due to the precession of the Moon's orbit.

- Geometrical Considerations: Astronomers use complex mathematical models to predict the path of solar eclipses. These models take into account the sizes of the Earth, Moon, and Sun, their distances from each other, and the speed at which they move in their orbits.


5. Historical and Cultural Significance


- Historical Observations: The paths of solar eclipses have been observed and recorded for millennia. Ancient civilizations often interpreted these events as omens or messages from the gods.

- Scientific Research: Modern science uses solar eclipses to study the Sun's corona and to test various astronomical theories, including Einstein's theory of general relativity.


6. Technological Advancements


- Satellite Observations: With the advent of space technology, satellites have provided us with detailed data on the Earth-Moon-Sun system, enhancing our ability to predict eclipse paths with great accuracy.


Conclusion

The paths of solar eclipses are a result of the intricate dance of celestial bodies governed by the laws of physics. Understanding these paths requires a grasp of orbital mechanics, the alignment of the Sun, Moon, and Earth, and the influence of various astronomical factors. Each eclipse is a unique event, shaped by the dynamic and ever-changing nature of our solar system.

Will our planet always have solar eclipses?

Solar eclipses are a fascinating celestial event where the Moon passes between the Earth and the Sun, temporarily obscuring the Sun's light. However, the phenomenon of solar eclipses as we know them will not be a permanent feature of Earth's celestial experiences. To understand why, we need to delve into several aspects of celestial mechanics, the evolving nature of the Earth-Moon system, and the long-term changes in Earth's orbit and axial tilt.

1. Orbital Mechanics and Moon's Recession**: The Moon is gradually moving away from the Earth due to tidal forces. This process, known as lunar recession, occurs at a rate of about 3.8 centimeters per year. As the Moon moves farther away, its apparent size in the sky slowly decreases. Currently, the Moon's apparent size is just enough to cover the Sun during a total solar eclipse. However, as the Moon continues to recede, there will come a time, billions of years in the future, when it will appear too small in the sky to completely cover the Sun. At that point, total solar eclipses will no longer occur, though partial and annular eclipses may still happen.

2. Changes in Earth's Rotation: The Earth's rotation is gradually slowing down due to tidal friction caused by the gravitational interaction with the Moon. This slowing rotation will lead to longer days and could have complex effects on Earth's orbital dynamics. Over extremely long timescales, this could influence the occurrence and nature of solar eclipses.

3. Axial Tilt Variations: The Earth's axial tilt, or obliquity, is not constant. It undergoes long-term variations between about 22.1 and 24.5 degrees over a cycle of approximately 41,000 years. These changes can affect the pattern of solar and lunar eclipses. While not directly preventing solar eclipses, these variations can alter their frequency and global visibility.

4. Orbital Eccentricity Changes: Earth's orbital eccentricity – the measure of how much its orbit deviates from a perfect circle – changes over time. These changes can slightly affect the Earth-Sun distance and, consequently, the apparent size of the Sun as seen from Earth. This, combined with the Moon's recession, can influence the occurrence of solar eclipses.

5. Sun's Evolution: On a much longer timescale, the evolution of the Sun as it ages will also play a role. Billions of years from now, as the Sun enters the red giant phase, its size and luminosity will dramatically increase, potentially engulfing the inner planets, including Earth. If Earth survives this phase, the nature of solar eclipses would be drastically different, if they occur at all.

6. Gravitational Interactions with Other Bodies: The gravitational interactions with other bodies in the solar system, such as planets, can cause slight perturbations in Earth's orbit and the Moon's orbit. Over very long timescales, these perturbations can accumulate, potentially affecting the occurrence of eclipses.

7. Potential Geological and Atmospheric Changes on Earth: Over geological timescales, changes in Earth's atmosphere or surface could also impact how we observe solar eclipses. For instance, significant atmospheric changes could alter the way sunlight filters through and is perceived on Earth.

In summary, while solar eclipses are a regular and awe-inspiring event in our current epoch, the intricate and dynamic nature of celestial mechanics and cosmic evolution dictates that they will not always be a feature of Earth's sky. The gradual changes in the Moon's orbit, Earth's rotation and orbit, and the Sun's lifecycle, all play a role in this eventual change. This transformation, however, spans over such a vast timescale that it lies far beyond the realm of human observation and into the deep future of our planet and solar system.

Alternatives to Eclipse Glasses

Solar Filters

Solar filters are specialized optical devices designed to safely observe and photograph the Sun by significantly reducing the intensity of sunlight. These filters are crucial for protecting both the eyes and the equipment used for solar observation, such as telescopes, binoculars, or cameras. Without a solar filter, looking directly at the Sun can cause permanent eye damage, and the intense sunlight can damage or destroy the internal components of optical devices.

Solar filters work by attenuating the solar radiation across a broad spectrum of light, including visible light, ultraviolet (UV) rays, and infrared (IR) radiation. This attenuation is necessary because the Sun emits intense light and energy across the entire electromagnetic spectrum, and exposure to these rays can be harmful.

There are several types of solar filters, each designed for specific applications and equipment:

1. Glass Solar Filters: These are made of specially coated glass that reflects or absorbs the harmful rays of the Sun. They often have a metallic coating that gives the Sun a yellow or orange tint when viewed through them.

2. Film Solar Filters: These are thinner and less expensive than glass filters. They are made from a flexible, optical-grade material with a metallic coating. Film filters are popular among amateur astronomers and photographers due to their affordability and ease of use.

3. Hydrogen-Alpha (H-Alpha) Filters: These are specialized filters designed for observing the Sun’s chromosphere. They only allow a narrow wavelength of red light to pass through, which is emitted by hydrogen in the solar atmosphere. This enables the viewer to see solar flares, prominences, and other chromospheric features.

4. White-Light Filters: These filters block a significant portion of the Sun’s light, allowing you to see the photosphere (the visible surface of the Sun). They provide a more “natural” view of the Sun, showing sunspots and surface granulation.

5. Solar Photography Filters: These are designed specifically for cameras and are used in solar photography. They often have a higher optical quality to ensure sharp images and can come in various forms, including screw-on filters for lenses or sheet filters that can be adapted to different camera systems.

6. Eclipse Glasses: These are a simple, portable form of solar filter. They are designed for direct viewing of the Sun, particularly during solar eclipses. Eclipse glasses are made from a special material that cuts down the Sun’s brightness, making it safe to look at.

It’s important to note that not all solar filters reduce light intensity to the same degree, and different filters are used for different types of solar observation. For instance, filters used for visual observation typically block out more light than those used for photography.

When using solar filters, it's crucial to ensure that they are free from damage, such as scratches or punctures, as even a small defect can allow harmful sunlight to pass through. Additionally, the filter must be securely attached to the viewing equipment to prevent accidental exposure to unfiltered sunlight.

In summary, solar filters are essential tools for safely observing and photographing the Sun. They protect the eyes and equipment by significantly reducing the intensity of sunlight, and they come in various forms tailored to different observational and photographic needs. Their use is critical in preventing eye damage and in enabling the observation of solar phenomena such as sunspots, solar flares, and eclipses.

Specialized Telescopes

Observing the Sun directly through telescopes is a fascinating and scientifically valuable activity, but it requires specialized equipment to do so safely and effectively. There are several types of telescopes and accessories designed for direct solar observation, each with its unique features and methods of operation. Here's an extensive look at the various kinds of telescopes and tools used for this purpose:

1. Dedicated Solar Telescopes: These telescopes are specifically designed for observing the Sun. They often have built-in filters that allow only a small fraction of the Sun's light to pass through, ensuring safe observation. A popular example is the Hydrogen-alpha (H-alpha) telescope, which filters light to the H-alpha spectral line, allowing detailed views of solar prominences, filaments, and other chromospheric features.

2. White Light Solar Filters: These are filters that can be attached to the front of a conventional telescope, blocking out the vast majority of sunlight and allowing only a very small, safe amount of light to pass through. They enable the observation of sunspots, solar granulation, and limb darkening. These filters are made from various materials, including Mylar and specialized glass, and must be free from any damage or pinholes to ensure safe solar viewing.

3. Solar Projection Boxes: This is a safer, indirect method of solar observation. A telescope is pointed at the Sun, and the image is projected onto a white surface or screen, usually inside a box, where it can be viewed and even traced. This method is particularly useful for group viewing or educational purposes.

4. Solar Scopes or Sunspotters: These are simple, portable telescopes with a built-in projection screen. They are specifically designed for safe solar viewing and are excellent for educational environments. They typically do not provide the same level of detail as more advanced setups but are very user-friendly.

5. Coronado Telescopes: These are a type of specialized solar telescope designed to observe the Sun in specific wavelengths of light, such as the H-alpha line. They are excellent for viewing solar flares, prominences, and other chromospheric phenomena.

6. Solar Digital Cameras and Imaging: Advanced solar observers often use specialized digital cameras or CCD cameras attached to their telescopes. These devices, combined with various filters, can capture detailed images of the Sun in different wavelengths, which can be processed to reveal intricate solar features.

7. Solar Observatories and Space-Based Telescopes: Professional solar observation often occurs in solar observatories, which house advanced and large-scale equipment. Space-based telescopes like the Solar Dynamics Observatory (SDO) or the Parker Solar Probe provide unprecedented views of the Sun from space, free from atmospheric interference.

8. Eyepiece Solar Filters: These are filters that attach to the eyepiece of a telescope. However, they are generally not recommended due to safety concerns. If these filters crack or fail during use, the observer's eyesight can be at serious risk.

9. Radio Telescopes: While not for direct visual observation, radio telescopes can observe the Sun in radio wavelengths. They can detect solar bursts and other phenomena that are not visible in the optical spectrum.

10. Spectroscopes: These are instruments used to analyze the Sun's spectrum. They can be attached to a telescope to disperse the sunlight into a spectrum for detailed study, revealing information about the Sun's composition and atmosphere.

Each of these methods and instruments offers a unique window into observing and understanding our closest star, the Sun. It's crucial to note that safety is paramount in solar observation. Looking at the Sun without proper equipment can lead to severe eye damage or blindness. Therefore, it's essential to use appropriate solar filters or indirect methods when observing the Sun.

Pinhole Projectors

The use of pinhole projectors for observing a solar eclipse is a fascinating and educational method that allows individuals to safely view this celestial event. To fully appreciate the significance and utility of pinhole projectors, it's essential to delve into various aspects including the nature of solar eclipses, the principles behind pinhole projection, the construction and use of pinhole projectors, safety considerations, and the educational value of this method.

1. Understanding Solar Eclipses:
- A solar eclipse occurs when the Moon passes between the Earth and the Sun, partially or completely blocking the Sun's light.
- There are three types of solar eclipses: total, partial, and annular. Each presents a unique visual phenomenon.
- Observing a solar eclipse is a rare opportunity, as it requires specific alignment of the Earth, Moon, and Sun.

2. The Dangers of Directly Viewing a Solar Eclipse:
- Looking directly at the Sun, even during an eclipse, can cause serious eye damage or blindness.
- The Sun's ultraviolet (UV) radiation can burn the retinas in the eyes leading to permanent damage or even blindness.
- This risk necessitates the use of safe viewing methods, such as pinhole projectors.

3. Principles Behind Pinhole Projection:
- Pinhole projection is based on the camera obscura effect, where light passes through a small opening (pinhole) and projects an inverted image on the opposite surface.
- The smaller the pinhole, the sharper the projected image, but it will also be dimmer.
- This method exploits the rectilinear propagation of light, meaning light travels in straight lines.

4. Constructing a Pinhole Projector:
- A simple pinhole projector can be made with common household items like two pieces of white card, aluminum foil, and tape.
- A pinhole is made in one piece of card or foil, and the other piece serves as a screen where the image is projected.
- The distance between the pinhole and the screen can be adjusted to change the size and focus of the image.

5. Using a Pinhole Projector:
- To use the projector, the viewer stands with their back towards the Sun.
- The pinhole is pointed towards the Sun, allowing sunlight to pass through and project an image of the Sun on the screen.
- During a solar eclipse, this projection will show the Moon passing across the Sun.

6. Safety Considerations:
- It's crucial to never look directly at the Sun through the pinhole.
- The pinhole projector should be used in a shaded area to enhance the visibility of the projected image.
- Children should be supervised to ensure they use the projector correctly.

7. Educational Value:
- Building and using a pinhole projector is an excellent educational activity for all ages.
- It provides a hands-on experience in understanding basic principles of optics and astronomy.
- Observing a solar eclipse in this manner can spark interest in science, particularly astronomy and physics.

8. Advantages of Pinhole Projectors:
- They are inexpensive and easy to make.
- They provide a safe way to view solar eclipses without risking eye damage.
- They can be a fun, communal activity, promoting group learning and discussion.

9. Limitations and Considerations:
- The projected image is relatively small and less detailed compared to other methods like telescope projection or eclipse glasses.
- Environmental factors like cloud cover or ambient light can affect the visibility of the projected image.

10. Broader Implications:
- The use of pinhole projectors ties into broader themes of human ingenuity in adapting simple principles to achieve practical outcomes.
- It reflects the enduring human curiosity about celestial events and the universe.
- Such simple yet effective tools democratize the experience of astronomical events, making them accessible to people regardless of their resources.

In conclusion, pinhole projectors offer a safe, educational, and enjoyable way to observe solar eclipses. They embody the application of basic scientific principles for practical use and provide an accessible means for people of all ages to engage with and learn about one of nature's most spectacular phenomena.

Welder's Glass

The use of welder's glass for the direct observation of a solar eclipse is a topic that encompasses various aspects, including the nature of solar eclipses, the importance of eye safety, the properties of welder's glass, and how it can be used effectively and safely for eclipse viewing.

Understanding Solar Eclipses:
A solar eclipse is a celestial event where the moon moves between the Earth and the sun, partially or completely blocking the sun's light. This can happen only during a new moon when the sun and the moon are in conjunction as seen from Earth. There are three types of solar eclipses: total, partial, and annular.

The Need for Eye Protection:
Observing a solar eclipse requires caution because looking directly at the sun can cause serious eye damage, including retinal burns. This is because the sun emits intense visible light and ultraviolet (UV) radiation. Even during an eclipse, when the sun is partially covered, its rays can be harmful.

Welder's Glass and Its Properties:
Welder's glass is a type of darkened glass used in welding helmets to protect the eyes from the bright light and UV radiation produced during welding. This glass is rated using a shade number, which indicates the level of darkness and the amount of light it allows to pass through. For solar eclipse viewing, a shade number of 14 or higher is recommended. This level of darkness sufficiently reduces the sun's brightness and blocks harmful UV and infrared (IR) radiation.

Why Welder's Glass is Suitable for Eclipse Viewing:
1. Adequate Filtration: Welder's glass of the appropriate shade number (14 or higher) filters out the harmful UV and IR radiation and reduces the sun's visible light to a safe level.
2. Accessibility: Welder's glass is a readily available and affordable option for many people.
3. Durability: The glass is designed to withstand high levels of light and radiation, making it a reliable tool for viewing solar phenomena.

How to Use Welder's Glass for Eclipse Viewing:
1. Ensure Proper Shade Number: Before using welder's glass for eclipse viewing, verify that it is shade number 14 or higher.
2. Inspect for Damage: Check the glass for any scratches, cracks, or damages. Even a small defect can reduce its effectiveness in protecting your eyes.
3. Use as a Viewing Filter: Hold the welder's glass in front of your eyes before looking up at the sun. Do not remove it while looking at the sun.
4. Avoid Prolonged Viewing: Even with protection, it's advisable not to look at the sun for prolonged periods. Take breaks to rest your eyes.
5. Do Not Use with Optical Devices: Welder's glass should not be used in conjunction with telescopes, binoculars, or cameras as these devices can concentrate the sun’s rays and damage the glass or your eyes.

Alternatives to Welder's Glass:
While welder's glass is effective, there are also other methods and tools for safe eclipse viewing, such as eclipse glasses made with solar filters, pinhole projectors, and telescopes or binoculars equipped with appropriate solar filters.

Educational and Safety Importance:
Using welder's glass for eclipse viewing not only provides a safe way to enjoy a spectacular natural phenomenon but also serves as an educational experience in understanding the importance of eye safety and the science behind solar eclipses.

In conclusion, welder's glass, when used correctly, offers a safe, effective, and accessible means for the direct observation of solar eclipses, allowing individuals to experience these remarkable events without risking eye damage. However, it's crucial to use the correct shade and to follow safety guidelines to ensure a safe and enjoyable eclipse viewing experience.

Cell Phone

Taking pictures of a solar eclipse with a cellphone camera is a unique and exciting opportunity, but it requires careful planning and execution to ensure both your safety and the safety of your device. Here’s a detailed guide on how to do it safely:


Understanding the Risks


1. Eye Safety: Looking directly at the sun, even during an eclipse, can cause permanent eye damage or blindness. This risk is present even when viewing through a camera lens.
2. Device Safety: Direct exposure to the intense sunlight can damage the camera sensor of your cellphone.


Preparing for the Eclipse


1. Research the Eclipse: Know the exact timing of the eclipse in your location. Eclipses have different phases, and total eclipses are rare.
2. Get the Right Equipment: Purchase a solar filter or eclipse glasses. These are essential for protecting your eyes and your camera’s lens.
3. Understand Your Cellphone Camera: Familiarize yourself with the camera settings. Manual settings can be more effective for capturing the eclipse.


Setting Up Your Equipment


1. Attach a Solar Filter: Secure a solar filter to your cellphone camera. This filter protects the camera’s lens from the intense solar rays.
2. Using a Tripod: A tripod stabilizes your phone, reducing blurriness. It’s especially useful for capturing the slow progress of an eclipse.
3. Practice Shots: Take practice shots at different exposures and settings to understand what works best for capturing the sun.


During the Eclipse


1. Protect Your Eyes: Never look directly at the sun without proper eye protection, even when using your cellphone camera.
2. Use the Camera’s Zoom Sparingly: Digital zoom can degrade image quality. If possible, use optical zoom or take wide shots and crop later.
3. Adjust Settings as Needed: Change the exposure settings as the light changes during the eclipse phases.
4. Capture Different Phases: Try to capture various stages of the eclipse – partial, total, diamond ring, and Baily's beads, if visible.


Post-Eclipse


1. Review and Edit: Check your images. Editing can enhance details that were not initially visible.
2. Share Your Experience: Share your photos with friends, family, or online communities interested in astronomy and photography.


Additional Tips


1. Battery and Memory: Ensure your phone is fully charged and has enough memory space.
2. Use a Remote Shutter Release: This reduces shake and blurriness when taking photos.
3. Backup Your Photos: Always back up your photos immediately to avoid accidental loss.
4. Join Photography Groups: Online groups can provide tips and share experiences on eclipse photography.
5. Learn from the Experience: Note what worked and what didn’t for future photography sessions.


Safety First


Always prioritize safety over getting the perfect shot. If you’re unsure about using your cellphone, consider enjoying the eclipse visually with proper eye protection and leaving photography to more equipped cameras.

Legal and Environmental Considerations


1. Respect Local Laws: Some areas may have specific regulations about photographing celestial events.
2. Be Environmentally Conscious: Ensure that your photography setup does not harm the natural environment around you.

Conclusion


Capturing a solar eclipse with a cellphone camera is challenging but rewarding. With the right preparation, equipment, and safety measures, you can safely photograph this spectacular celestial event and create lasting memories. Remember, the safety of your eyes and preserving the condition of your cellphone should be your top priorities.

April 2024 Eclipse

Which states will be along the path of totality?

The total solar eclipse in April 2024 will pass through several U.S. states. The path of totality, where the eclipse will be fully visible, includes parts of the following states:

1. Texas: The path of totality enters the United States through Texas, providing an excellent view of the eclipse in cities like Dallas and Austin.

2. Oklahoma: Moving northeast, the eclipse will be visible in parts of Oklahoma, including cities like Tulsa.

3. Arkansas: The eclipse will then pass through Arkansas, offering views in cities like Little Rock.

4. Missouri: Continuing northeast, Missouri, including St. Louis, will experience the total eclipse.

5. Illinois: Parts of Illinois, including Carbondale, which also experienced totality during the 2017 eclipse, will witness the event.

6. Kentucky: The path of totality will pass through Kentucky, including cities like Paducah.

7. Indiana: The eclipse will be visible in parts of Indiana, including Indianapolis.

8. Ohio: Ohio will experience the eclipse, with cities like Dayton and Cleveland in the path of totality.

9. Pennsylvania: The path then crosses into Pennsylvania, including Erie.

10. New York: Moving further northeast, the eclipse will be visible in parts of New York, including Buffalo and Rochester.

11. Vermont: The eclipse will be visible in northern parts of Vermont.

12. New Hampshire: Parts of New Hampshire will experience the total eclipse.

13. Maine: Finally, the path of totality exits the United States through Maine, providing views in cities like Caribou.

The eclipse will offer a spectacular view in these states, with numerous communities along the path planning events and activities to celebrate and observe this rare astronomical event.

What time will the April 2024 eclipse occur?

The total solar eclipse on April 8, 2024, will be visible from various locations across North America. The timing of the eclipse will vary depending on the location:

1. The eclipse will begin over the South Pacific Ocean and cross through Mexico, the United States, and Canada. In Mexico’s Pacific coast, totality will start around 11:07 a.m. PDT.

2. In the United States, the path of totality will begin in Texas at 1:27 pm CDT and end in Maine at 3:35 pm EDT.

3. A more detailed timeline of the eclipse, using UTC and local time in San Antonio as a reference, is as follows:
- First location to see the partial eclipse begin: April 8 at 15:42:15 UTC (10:42:15 am in San Antonio).
- First location to see the full eclipse begin: April 8 at 16:38:52 UTC (11:38:52 am in San Antonio).
- Maximum Eclipse: April 8 at 18:17:21 UTC (1:17:21 pm in San Antonio).
- Last location to see the full eclipse end: April 8 at 19:55:35 UTC (2:55:35 pm in San Antonio).
- Last location to see the partial eclipse end: April 8 at 20:52:19 UTC (3:52:19 pm in San Antonio).

These times provide a general guideline for when the eclipse will occur. However, the specific timing and duration of the eclipse can vary depending on your exact location along the path of totality. For the most accurate information, it's advisable to refer to local astronomical resources or use applications and websites dedicated to eclipse tracking.

How long will the April eclipse last for?

The total solar eclipse in April 2024 will last for 4 minutes and 28 seconds. This event is scheduled to occur on April 8, 2024. The longest duration of totality, lasting 4 minutes and 28.13 seconds, will be observed near the town of Nazas, Mexico.

Can I view this eclipse without ISO certified eclipse glasses?

Technically, yes. During totality, which will last for 4 minutes, you can safely take off your glasses and view the totality. But before and after totality, you MUST wear your glasses in order to prevent eye damage.

Safety Glasses

Are your safety glasses safe?

Yes, our safety eyewear, and many of our sunglasses models also, meet ANSI Z87.1+ standards for impact resistance.

Sunglasses

Are your sunglasses safe?

Yes. Our sunglasses use UV400 lenses, which are designed to protect your eyes from harmful UV.

Running and Cycling Glasses

Are your running or cycling glasses safe?

Yes. Most of our models meet ANSI Z87.1+ requirements. In addition, we offer models with Type 0, 1, 2, and 3 lenses depending on your specific application.

Blue Light Glasses

Are your blue light glasses safe?

Yes, our blue light glasses (BLG) use TR90 lenses.

How much blue light do your glasses filter?

We only sell blue light glasses that filter at least 30% of blue light, with some models filtering 40%. Less than 30% is presumably not useful for eye strain.