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I'm lucky enough to be where an annular eclipse will happen at the same time as sunrise. Usually, it's dangerous to look at an eclipse directly. However, the sun appears much less bright at sunrise.

Is it safe to look directly at an annular eclipse at sunrise?

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    $\begingroup$ Rather than downvoting (which some have done), this question is worthy of an upvote because people on the US East Coast will be looking at the eclipsed Sun at sunrise this morning without eye protection. That said, this is a duplicate. If the Sun is in the sky it is hazardous to look at the Sun, even briefly. Even if the Sun is being eclipsed, it is hazardous to look at the Sun, even briefly. $\endgroup$
    – David Hammen
    Commented Jun 10, 2021 at 11:24

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To look at an eclipse is never more dangerous than to look at the normal sun. Sun has uv radiation that can damage the light receptors of the retina. During the noon the sun is directly above our head; sunlight has to travel a short distance through our atmosphere and hence more UV photons that enter our eyes.

During sunrise or sunset, sunrays have to travel a much longer distance through the atmosphere. A lot of UV and other photons are scattered and filtered before they reach our eyes and hence sunlight is much dimmer compared to at noon.

During eclipse' the number of photons are even less than the normal sun. Hence, safer. Although it would only be safe to look at the sunrise/eclipse during sunrise for a few seconds, it is not advisable to do so. You should use some extra safety (solar filters) when looking at an eclipse.

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    $\begingroup$ "To look at an eclipse is never more dangerous than to look at the normal sun." That's not exactly true. If the eclipse is close to total, so that the sky is noticeably dark, then looking directly at the eclipse can be more dangerous, as I explain here: astronomy.stackexchange.com/a/36630/16685 $\endgroup$
    – PM 2Ring
    Commented Jun 10, 2021 at 7:56
  • $\begingroup$ OTOH, if the annular / partial eclipse only makes the sky slightly darker, then viewing it at sunrise (or sunset) is no more dangerous than looking at a regular sunrise or sunset. However, as I mention in the linked answer, people tend to look at an eclipse sunrise / sunset for longer than a regular sunrise / sunset. $\endgroup$
    – PM 2Ring
    Commented Jun 10, 2021 at 7:59
  • $\begingroup$ It makes sense that the pupils will dilate because of dark sky. But isn't it also true that most of the photons are blocked by the moon during a total solar eclipse? And during a partial/Annular eclipse some of the photons are blocked? And people do tend to look longer during an eclipse but that is exactly why is said "it is not advisable to look at an eclipse even during sunrise/sunset". We should use proper solar filters to do so. $\endgroup$
    – Aryan Bansal
    Commented Jun 10, 2021 at 9:12
  • $\begingroup$ Yes, it's safe to view an eclipse during totality without a filter, but just before and just after totality is when it's most dangerous, due to the pupil dilation. Of course, a partial or annular eclipse is (by definition) never total, and the light not blocked by the Moon is still dangerous. However, when rhe Sun is very close to the horizon, the short wavelengths are highly scattered, which is why the Sun looks red, so the proportion of UV in that red light is much lower than when the Sun is high in the sky. $\endgroup$
    – PM 2Ring
    Commented Jun 10, 2021 at 9:30

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