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Deborah Byrd

An unusual shot of anticrepuscular rays

It looks like ordinary crepuscular rays are coming from the reflected sunlight at the base of this mountain. But that’s not what’s happening in this rare photo.

Why do comets emit X-rays? Mystery solved

Researchers fired laser beams onto a plastic foil to mimic some of the conditions comets encounter as they travel through our solar system and to solve a long-standing mystery.

March equinox: All you need to know

Happy equinox! The March 20, 2018, equinox is an event that happens on our sky’s dome and a seasonal marker in Earth’s orbit around the sun.

Are day and night equal at the equinox?

Equinox means “equal night.” And you might hear day and night are equal at the equinoxes. Yet Earth’s air and our sun conspire to give us more daylight at an equinox.

Researchers say 1st interstellar asteroid likely from double star

New research suggests that the 1st confirmed interstellar asteroid – called ‘Oumuamua by astronomers – likely came from a system where 2 stars orbit each other.

How can you know what to believe?

It’s not surprising that a new study linking extreme winter weather in the U.S. East with a warmer Arctic has drawn fire from global warming skeptics. Should you believe the study or the skeptics?

See it! Young moon, Venus, Mercury

Wow! So many of you are catching the moon, Venus and Mercury after sunset. Thank you for all your photos. We wish we could post them all!

Researchers explore the voids between superclusters

An analysis of the cosmic microwave background has provided clues about the gas inside vast cosmic voids in space, between giant superclusters of galaxies.

The Beehive: 1,000 stars in Cancer

On a dark night, look for it as a smudge of light, with 3 times the moon’s diameter. It’s really a wondrous cluster of stars called the Beehive, or M44.

Where did Mars get its organic molecules?

New computer simulations indicate 1/3 of Mars’ organic molecules come from asteroids and comets.