NASA has basic safety advice for those able to view today's solar eclipse:
Except during the brief total phase of a total solar eclipse, when the Moon completely blocks the Sun’s bright face, it is not safe to look directly at the Sun without specialized eye protection for solar viewing.
Viewing any part of the bright Sun through a camera lens, binoculars, or a telescope without a special-purpose solar filter secured over the front of the optics will instantly cause severe eye injury.
When watching the partial phases of the solar eclipse directly with your eyes, which happens before and after totality, you must look through safe solar viewing glasses (“eclipse glasses”) or a safe handheld solar viewer at all times. Eclipse glasses are NOT regular sunglasses; regular sunglasses, no matter how dark, are not safe for viewing the Sun. Safe solar viewers are thousands of times darker and ought to comply with the ISO 12312-2 international standard. NASA does not approve any particular brand of solar viewers.
Always inspect your eclipse glasses or handheld viewer before use; if torn, scratched, or otherwise damaged, discard the device. Always supervise children using solar viewers...
Speaking of children, don't do what this Very Stable Genius bad seed did during the 2017 eclipse (after being told not to):
There's more advice from NASA at the link above.
(Photo: Don't be like dumbass here.)
