Blue Moon over Houston Thursday Evening

When the full moon rises over Texas this Thursday evening it will be the second full moon this month. Astronomers refer to that as a "blue moon."  It's unknown when the phrase was first used, some speculate it's been around for about 400 years. But it has nothing to do with the color of the moon and more to do with events that rarely happen, as in "Once in a Blue Moon."

However, people who photograph the moon on a regular basis have occasionally captured the lunar disk in shades of blue. Tom King of Watauga,Texas shot the image included here. He speculates moisture in the air at the time the moon was rising caused the blueish color. But chances are the moon on Thursday will look like it normally does.

The lunar calendar runs 29 days compared to the 30/31 days in our months. That means we usually only have one full moon each month, although occasionally we end up with two. There's nothing weird going on here. It's just a matter of timing.

An added bonus tonight, you'll see the bright planet Jupiter right next to the full moon.  If you have a telescope you might even be able to see the craters and mountains on the planet's surface.

Note: The times on the lunar calendar linked above are in Universal Time. Subtract 5 hours to calculate the moonrise and moonset in Central Daylight Time; subtract 6 hours for Central Standard Time.

Comments

[Tim Heller]

You can't believe everything you read in Wikipedia. Information is not checked for accuracy. This is an example of that. If you click on the link embedded in my initial report, you'll see that references to a "Blue Moon" have been around for about 400 years.

[Joe Kanusky]

For Tim Heller: Please go to the following web site for further information on a "blue moon." http://en.wikipedia.org/wiki/Blue_moon
Here is a quote: "In recent times, people have taken to calling a full moon a blue moon based on the Gregorian calendar. By this use of the term, a blue moon is the second of two full moons to occur in the same calendar month. This definition of blue moon originated from a mistake in an article in the March 1946 Sky & Telescope magazine, which failed in an attempt to infer the earlier definition used in the original Farmer's Almanac (see above). It was helped to popularity when Deborah Byrd of Earth & Sky walked into the Peridier astronomy library at the University of Texas at Austin one day, leafed through some old magazines, and found the 1948 blue moon article in Sky & Telescope. She used the definition – the second full moon in a single month – in the radio series Star Date for some years. As a result, the game Trivial Pursuit used a question and answer about "blue moon". Sky & Telescope discovered the error nearly sixty years later and the magazine printed a retraction and correction.[2] By the time the correction came the calendar definition had already come into common use. As it is easier to understand, the mistaken calendar-based meaning has stuck."

[Tim Heller]

By my calculations, the next Blue Moon will be on December 31, 2009.

[Travis]

When was the last blue moon? Wasnt it like 04? When will the next one be?