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How often do we have a Blue Moon in July?

Image credit: Tim Geers

Image by Flickr user Tim Geers

How often do we have a Blue Moon in July? For the answer, you have to look to a concept from astronomy and calendar studies, at what’s called the Metonic cycle.

California’s rain debt equals full year’s precipitation

California's accumulated precipitation “deficit” from 2012 to 2014 shown as a percent change from the 17-year average based on TRMM multi-satellite observations. Image credit: NASA/Goddard Scientific Visualization Studio

California’s accumulated precipitation “deficit” from 2012 to 2014 shown as a percent change from the 17-year average based on TRMM multi-satellite observations. Image credit: NASA/Goddard Scientific Visualization Studio

California’s accumulated “rain debt” is now equal to an average full year of precipitation, according to a new NASA study.

Exciting news! Astronomical League and EarthSky join forces

Greg Hogan created this image.  Isn't it great?  Thanks, Greg!

An EarthSky community member, Greg Hogan, created this image. Thanks, Greg!

Popular astronomy website and nation’s largest federation of astronomy clubs have joined forces to to bring the night sky’s wonder, beauty, and mystery to the public.

Comet Tempel 1 and Deep Impact

View larger. | NASA's 'Deep Impact' probe's historic appointment with Comet Tempel 1 on July 4, 2005.  Artist's concept by Marco Nero in Sydney, Australia

NASA’s ‘Deep Impact’ probe’s historic appointment with Comet Tempel 1 on July 4, 2005. Artist’s concept by Marco Nero in Sydney, Australia

Artist’s concept of first-ever earthly space probe to impact a comet’s surface. Learn more about this mission, and see an actual image of the impact itself, inside this post.

Video: The science of dogs

The newest video from AsapSCIENCE is for dog lovers. That is, for everyone!

Blue Moon – second July full moon – on July 31

Patrick Casaert – whose community on Facebook is called La Lune The Moon – used a blue filter to capture this shot of the moon on July 27, 2015.

Patrick Casaert used a blue filter to capture this shot of the moon on July 27, 2015.

Blue Moon coming! As seen in the photo above by Patrick Casaert, the moon has been waxing to full this week. Patrick used a blue filter to create his moon photo, and if you see the moon in tonight’s sky, you’ll see it’s nearly full … but not at all blue in color. Yet, as the second full moon for the month of July, many will call it a Blue Moon.

Impacts of climate change on human health

Image credit: Lancet Commission

Image credit: Lancet Commission

A new report published in The Lancet finds that “tackling climate change could be the greatest global health opportunity of the 21st century.”

Found! First aurora beyond solar system

View larger. | Artist conception of an aurora over the polar region of a brown dwarf. Image via Chuck Carter and Gregg Hallinan, Caltech.

Artist concept of an aurora over the polar region of a brown dwarf. Image via Chuck Carter and Gregg Hallinan, Caltech.

The brown dwarf LSR J1835+3259 has now been found to have a powerful aurora, the first aurora seen beyond our solar system and the most powerful aurora ever seen. This aurora is 10,000 times more powerful than any astronomers have witnessed before.

Largest dinosaur with birdlike wings and feathers

Fossil remains of large winged dinosaur Zhenyualong Suni.  This nearly complete skeleton was found in northeast China’s Liaoning province.  , Image via Junchang Lu and Stephen Brusatte via Science.

Fossil remains of large winged dinosaur, named Zhenyualong Suni. This nearly complete skeleton was found in northeast China’s Liaoning province. Image via Junchang Lu and Stephen Brusatte via Science.

Discovery of largest-ever winged dino in China, from 125 million years ago. It was sleek and birdlike with feathers on its arms and torso, but it could not fly.

Solar halo over Sweden

View larger. | Visit Fotograf Goran Strand on Facebook.

Solar halo around a statue, by Göran Strand.

Halos are a sign of high thin cirrus clouds drifting high above our heads. The clouds contain millions of tiny ice crystals, which both refract (split) and also reflect sunlight. Read more about this photo, inside.