Caoimhín's Content

The Moon is one of the most prominent objects in the sky. There are only a few days each month where the Moon isn’t at least a little visible for some part of the day or night, and when the Moon is full it dominates the sky. In this video, we’re going to take a look at some of the more subtle ways the Moon changes over the course of the night.

Firstly, we deal with the more subtle changes in phase, how much the Moon can vary in just one night, but also within a night. The Moon’s phases are continuously shifting, changing a few fractions of a percent during the night each night, though this can of course be hard to see.

We also look at the Moon’s motion across the sky between nights. Here, the Moon will move from its position close to Saturn, across the sky towards Jupiter as we move into October.

The planets all travel across the same plane or line in our sky, the ecliptic, but the Moon follows a slightly different path, orbiting the Earths equator. We look at how the Moon moves relative to that line, crossing over it as it moves from below the line to above it, here shown with the the Moon starting below Saturn but ending up over Jupiter.

All these subtle motions contribute to eclipses, and with one coming up in late October, it’s only fair that we should move forward and take a look. We take a close look at the partial eclipse occurring on the 28th of October, so you have plenty of advanced warning to go and take a look yourself, but also to make sure you see the eclipse somehow just in case it’s cloudy on the night itself.

Of course, there’s plenty of other tidbits in the video, such as a guide on spotting the Sea of Tranquility, in English to balance out the Irish description last week. I have to leave some details as a reward for watching after all.