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Deborah Byrd
Photo submitted to EarthSky byJoe Tabb.

Iridescent cloud over Kentucky

Iridescent clouds appear in the same direction as the sun. Rainbow-like colors appear irregularly over the clouds in the form of colored edges, spots and bands.

Artist's concept of a greenhouse on the surface of Mars via SAIC/ NASA.

Can we grow food on Mars?

Apparently we can, and you can view details in this video from a talk given at Mars One’s recent private event in Amsterdam.

Marathon Valley on Mars opens to a view across Endeavour Crater in this scene from the Pancam of NASA's Mars rover Opportunity. The scene merges many exposures taken during April and May 2016. The view spans from north (left) to west-southwest. Its foreground shows the valley's fractured texture. Image via NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

Video sweep across Mars’ Marathon Valley

A panoramic view from the Mars rover Opportunity. Wow! This video will take you to another world …

Corona Borealis, the Northern Crown, with its brightest star Alphecca, via Fred Espenak and AstroPixels. Used with permission.

Star of the week: Alphecca

Alphecca. Gemma. Alpha Coronae Borealis or simply Alpha Cor Bor. They’re all names for one star – the brightest star in the constellation Northern Crown.


Ophiuchus and Serpent on June evenings

Ophiuchus the Serpent Bearer is one constellation that looks to me like what it’s supposed to be: a big guy holding a snake.

Artist's impression of the simultaneous stellar eclipse and planetary transit events on Kepler-1647. Such a double eclipse event is known as a syzygy. Image via Lynette Cook

Largest planet yet orbiting 2 suns

Imagine seeing 2 suns in your sky. Like the fictional planet Tatooine in Star Wars, some planets do orbit 2 stars. Kepler-164 is the largest yet discovered.

The HiRISE camera in orbit around Mars caught Mars Curiosity rover, just left of center in this image, on March 25, 2016 (MSL Sol 1291). Image via University of Arizona.

One robot spacecraft spies another

See the Mars rover Curiosity, nestled on Mars’ surface? The sharp-eyed HiRISE camera aboard the Mars Reconnaissance Orbiter caught the view from space.

You know it's hot when ...  Image via Flickr Flickr/Katerha

Why hottest weather isn’t on longest day

Solstice 2016 – longest day for us on northern Earth – was Monday. But the hottest weather is still to come for us in the Northern Hemisphere. Why?

NASA’s New Horizons spacecraft spied extensional faults on Pluto, a sign that the dwarf planet has undergone a global expansion possibly due to the slow freezing of a sub-surface ocean. A new analysis by Brown University scientists bolsters that idea, and suggests that ocean is likely still there today. Image credit: NASA/JHUAPL/SwRI.

Liquid water ocean under Pluto ice?

“That you could have vast liquid water ocean habitats so far from the sun on Pluto – and on other Kuiper belt objects as well – is absolutely incredible.”

Waning gibbous moon just after midnight on the morning of June 23, 2016 by Deirdre Horan of Dublin, Ireland.

Where’s the moon? Waning gibbous

A waning gibbous moon rises in the east late at night. You might see it in the west in early morning, floating against the pale blue sky.