Earthdata Forum

On Aug 16, 2017

I wanted to know why we cannot see the moon during solar eclipses on the march 9th 2016 images...the EPIC camera is 4 times further away from the earth than the moon and the shadow from the eclipse is clearly visible...please explain to me where the moon is in the image and why we cannot see it, the moon was supposed to be along the ecliptic plane that day as it passed over which would put it directly at the center of the earth from the L1 EPIC field of view.

On Aug 17, 2017 the DSCOVR Team posted

The angle between EPIC and the Sun on March 9th 2016 is 8.78 degrees. If we see the shadow, we cannot see the moon. Note that the angular size of the Earth is around 0.5 degrees.

The Moon and the Sun have different diameters, and the Sun is many times the size of the Moon. But as the Moon is closer to the Earth, the angular size of its disk appears to be the same as that of the Sun. That is why when the Moon is on the line between the Earth and the Sun, it eclipses the Sun, which becomes invisible from the Earth. Sometimes the trajectory of the shadow passes through inaccessible or remote territories of the Earth's surface. But in some cases, astronomical observatories and densely populated cities appear on the trajectory of the shadow, which makes it easier to observe eclipses.

Apologies. You were making a statement not asking a question.