jump to navigation

Blue Moon of May May 19, 2016

Posted by aquillam in Astronomy, MichiganAstro, Urban Observing.
Tags: , , ,
trackback

The Moon will be full on May 21, and according to some, it’ll be a blue moon. Now if you’re familiar with the common definition of a blue moon, you’ll look at that date and say “hey, that can’t be a blue moon!” That’s because the modern, common definition of a blue moon is the second blue moon in a single month. Since it takes about 29.5 days for the Moon to go through a cycle of phases, the earliest date for a blue moon is the 29th of the month.

However, there’s another definition of blue moon: the third of four full moons in a season. The seasons start on an equinox or solstice, and are 3 months long, so they normally have 3 full moons. The current season (spring) started on March 20 at 12:30 AM and the first full moon after that was on the 23rd. Spring will end on June 20 at 6:34 PM, just 12.5 hours after the moon is full. If you’re curious for more, EarthSky has the next few blue moons (of both types) and references for further reading.

If you want to observe, the full moon is just about the worst time. The bright light washes out the sky around it, and the glaring noon (on the Moon) light makes it hard to see any surface features. So much for astronomy. However,if you like atmospheric phenomena or optical illusions, it’s great. A full moon is much more likely to give you a moon-bow, arcs, or rays. And if you like the moon illusion, only the June full moon will be better at tricking your mind.

Advertisements

Comments»

No comments yet — be the first.

Leave a Reply

Please log in using one of these methods to post your comment:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: