Monthly Notes

June 10th, 2021 Annular Solar Eclipse

In the US, only those living in the eastern part of the US will get a glimpse of an annular solar eclipse at sunrise on the 10th. It will not be visible for those in the midwest or west. An annular solar eclipse is when the Moon is completely in front of the Sun but does not completely cover the Sun, so there is a ring of Sun or “fire” that peeks through. This is not a total solar eclipse, which is when the Moon completely blots out the Sun, but occurs when the Moon is farther out in its elliptical orbit and is thus slightly smaller than the Sun (as they appear in the sky). It is amazing that the Moon and Sun appear as the same size in the sky but slight differences in the distance that the Moon is from the Earth (caused by the elliptical orbit of the Moon around the Earth) can make the Moon slightly larger or smaller than the size that the Sun appears in the sky.


July 12/13, 2021 • Conjunction of Venus and Mars—when two planets appear very close together in the night sky.

In the early evening of July 12/13, within 1.5 hours after sunset, Venus and Mars will appear very close to one another, lower in the western sky. You can’t miss Venus because it is very bright! And, you will have to wait until the sky is somewhat dark to see the fainter Mars. There will be a few days before and after the 12/13th that they will be close but not as close as on these dates. You will easily be able to see the separation with your naked eyes. Now, the only “problem” is that Mars is not very bright at this time but Venus is, so the contrast here will be pretty great. And, on average, the planets do not twinkle, so Mars should be fairly steady in it brightness but expect some twinkling because it is close to the horizon, where the atmosphere is thicker.

The Pleiades or Seven Sisters

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