Tomorrow night (March 19th), there will be a full moon. But this full moon is special–and, for most of my readers (probably), a new phenomenon. You see, not only will tomorrow night’s moon be a full moon, but it will also be a perigee moon, meaning the moon will be about as close to Earth as it ever gets (it’s actually about an hour off, but close enough for our purposes). What does this mean? It means that tomorrow’s moon is going to appear 14% larger and noticeably brighter than the more distant full moons. The best time for viewing will be late evening or early nighttime, when the moon is “low-hanging” (or closer to the horizon).
A neat video about this, produced by NASA and loaded onto YouTube, was sent to me by a reader. (HT: Emre Guzelsu)
Some of you may be asking “What does this have to do with anything?” That’s a perfectly fair question, and a large part of the impetus for this post is the coolness factor (well, nerd-coolness). But it’s also an important reminder that celestial bodies don’t travel in circles, and on any given day one of Earth’s neighbors could be relatively close or distant. These distance cycles are almost completely ignored by all but a few astronomers and engineers, but they are incredibly important when designing space missions (for the obvious reason), which means they should have an effect on space policy and exploration. So the next time you hear an astronomer say something like “You know, next year would be a really good time to get a Mars mission together…” don’t shrug it off and wait until next year. If a goal is in the neighborhood, take advantage of it (good advice for life as well). Waiting for the next equally good opportunity can take a while…and to poetically illustrate my point, the last perigee full moon was about 28 years ago.
(PS – The title of this post is a shameless effort to make this blog more attractive to search engines. Hey, at least it’s on topic.)
