Image and Information Credits: NASA
More than 300 million people in the United States potentially could directly view the Aug. 21 total solar eclipse, and NASA wants everyone who will witness this celestial phenomenon to do so safely.
That Monday, a partial eclipse will be visible in every state. A total solar eclipse, which is when the Moon completely covers the Sun, will occur across 14 states in the continental U.S. along a 70-mile-wide (112-kilometer-wide) swath of the country.
It’s common sense not to stare directly at the Sun with your naked eyes or risk damaging your vision, and that advice holds true for a partially eclipsed Sun. But, only with special-purpose solar filters, such as eclipse glasses or a handheld solar viewer, you can safely look directly at the Sun.
NASA recommends that people who plan to view the eclipse should check the safety authenticity of viewing glasses to ensure they meet basic proper safety viewing standards.
Eclipse viewing glasses and handheld solar viewers should meet all the following criteria:
· Have certification information with a designated ISO 12312-2 international standard
· Have the manufacturer’s name and address printed somewhere on the product
· Not be used if they are older than three years, or have scratched or wrinkled lenses
· Not use homemade filters
· Ordinary sunglasses — even very dark ones — should not be used as a replacement for eclipse viewing glasses or handheld solar viewers
NASA has coordinated with medical and science professionals to provide additional safety information.
- Always inspect your solar filter before use; if scratched or damaged, discard it. Read and follow any instructions printed on or packaged with the filter.
- Always supervise children using solar filters.
- Stand still and cover your eyes with your eclipse glasses or solar viewer before looking up at the bright sun. After looking at the sun, turn away and remove your filter — do not remove it while looking at the sun.
- Do not look at the uneclipsed or partially eclipsed sun through an unfiltered camera, telescope, binoculars, or other optical device.
- Similarly, do not look at the sun through a camera, a telescope, binoculars, or any other optical device while using your eclipse glasses or hand-held solar viewer — the concentrated solar rays will damage the filter and enter your eye(s), causing serious injury.
- Seek expert advice from an astronomer before using a solar filter with a camera, a telescope, binoculars, or any other optical device. Note that solar filters must be attached to the front of any telescope, binoculars, camera lens, or other optics.
- If you are within the path of totality (https://go.nasa.gov/2pC0lhe (link is external)), remove your solar filter only when the moon completely covers the sun’s bright face and it suddenly gets quite dark. Experience totality, then, as soon as the bright sun begins to reappear, replace your solar viewer to look at the remaining partial phases.
- Outside the path of totality, you must always use a safe solar filter to view the sun directly.
- If you normally wear eyeglasses, keep them on. Put your eclipse glasses on over them, or hold your handheld viewer in front of them.
More than 6,800 libraries across the U.S. are distributing safety-certified glasses. Many are working with scientists to hold viewing events and activities before and during the eclipse. For a listing of participating libraries, visit:
NASA Television is offering a special live program, “Eclipse Across America: Through the Eyes of NASA” with real-time coverage of the event from coast to coast. The nearly four-hour program will include unprecedented images of the Aug. 21 eclipse from numerous spacecraft — including the International Space Station – high-altitude aircraft and balloons, and ground observations. Each will offer a unique vantage point for the eclipse. Additionally, the broadcast will include live coverage of activities in parks, libraries, stadiums, festivals and museums across the nation, and on social media. To watch the Aug. 21 NASA TV eclipse broadcast online and access interactive web content and views of the eclipse from these assets, visit: