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Next Blue Moon is May 21, 2016

Beautiful image by our friend Jv Noriega. Thank you, Jv! Does a Blue Moon look blue like this? No. This photo was made using special filters to create the blue color.

The next Blue Moon will be on May 21, 2016. It’s a seasonal Blue Moon, the third of four full moons between the March equinox and the June solstice of 2016. Read about the various kinds of Blue Moons, and how often they occur, here.

Hailstorm over Cambridgeshire, UK

View larger. | Photo credit: Andy Howard

View larger. | Photo credit: Andy Howard

Andy Howard said:

We don’t often see such contrast in the sky, but this we had to stop and snap on the iPhone.

Where is the Milky Way on May evenings?

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Where is the starlit band of the Milky Way on these May evenings? That luminous band of stars crossing the dome of sky is nowhere to be seen during the evening hours in May. Why? The disk of our Milky Way galaxy is shaped like a pancake. On May evenings, the plane of the pancake-shaped galactic disk coincides with the plane of the horizon. Because the Milky Way rims the horizon in every direction in the evening in May, we can’t see this roadway of stars until later at night right now.

Did human limbs evolve from shark gills?

Skeleton of an embryonic bamboo shark, viewed from the underside. Gill arch appendages extend from each side of the head. Directly below them are a pair of fins. Image credit: Andrew Gillis.

Skeleton of an embryonic bamboo shark, viewed from the underside. Gill arch appendages extend from each side of the head. Directly below them are a pair of fins. Image via Andrew Gillis.

The Sonic Hedgehog gene drives embryonic development of mammal limbs and shark gills. Could our limbs have evolved from gills?

Late April sun pillar

View larger. | Photo credit; Jesse Jackson

View larger. | Photo credit; Jesse Jackson

Jesse Jackson saw this sun pillar near Tucson, Arizona. “Talk about a ray of sunshine,” he said.

Faint star in Bootes makes history

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In 2007, a faint star in the constellation Bootes the Herdsman made astronomical history. An international team of astronomers, led by Jean-Francis Donati and Claire Montau of France, caught the star Tau Boötis flipping its north and south magnetic poles. These astronomers had been mapping the magnetic fields of stars. It was the first time a magnetic reversal had been observed on any star other than our sun.

Breakthrough Starshot aims for Alpha Centauri

Photo via BreakthroughInitiatives.org.

The dream of traveling to the stars is alive and well. Artist’s concept via BreakthroughInitiatives.org.

Breakthrough Starshot seeks proof of concept for a 100-million-mile-per-hour mission – using light-propelled nanocrafts – to reach the nearest star in 20 years.

How long would it take to get to Alpha Centauri?

Credit: Mark Rademaker/Mike Okuda/Harold White/NASA.

What a spaceship with warp drive might look like. Credit: Mark Rademaker/Mike Okuda/Harold White/NASA.

Alpha Centauri is the nearest star system to our sun at 4.3 light-years away. That’s about 25 trillion miles (40 trillion km) away from Earth – nearly 300,000 times the distance from the Earth to the sun. How might we travel to Alpha Centauri, the next-nearest star? And how long would it take to get there? Read about star travel via conventional propulsion, warp drives, and more.

Last quarter moon rises around midnight

The last quarter moon rises in the middle of the night and sets in the middle of the day. Photo by Lilliana Mendez of North Bergen, New Jersey.

The last quarter moon rises in the middle of the night and sets in the middle of the day. Photo by Lilliana Mendez of North Bergen, New Jersey.

You might spot it after sunrise on April 30, high in the sky. Did you know a last quarter moon is slightly fainter than a first quarter moon? Learn why here.

Did Earth’s magnetic field collapse for 2 hours on April 23?

An illustration of Earth’s magnetic field shielding our planet from solar particles. Image via NASA/GSFC/SVS.

An illustration of Earth’s magnetic field shielding our planet from solar particles. Image via NASA/GSFC/SVS.

No, Earth’s magnetic field did not collapse for 2 hours on April 23. The erroneous story – which is still spreading – came from a glitch in a computer simulation.