Io, the innermost of Jupiter's four large "Galilean" moons, is about the same size as Earth's moon, some 2,300 miles across, but it is very different than our moon. So different it is the only other…

Scientists have recently gathered some of the strongest evidence to date to explain what makes the sun's outer atmosphere so much hotter than its surface. The new observations of the small-scale…

Astronomers using NASA's Hubble Space Telescope have unexpectedly discovered the most distant galaxy that acts as a cosmic magnifying glass. Seen here as it looked 9.6 billion years ago, this monster…

Observations by NASA's Fermi Gamma-ray Space Telescope of several stellar eruptions, called novae, firmly establish these relatively common outbursts almost always produce gamma rays, the most…

Does this galaxy make me look fat? Has Andromeda been taking skinny selfies? It turns out the way some astrophysicists have been studying our galaxy made it appear that the Milky Way might be more…

New findings have resolved a decades-old puzzle about a fog of low-energy X-rays observed over the entire sky. Thanks to refurbished detectors first flown on a NASA sounding rocket in the 1970s,…

I thought I'd post this, because, though it is obvious to most people in the field -  there are many who still think that present day life on the surface of Mars is impossible because of UV…

In June of 2013, an exceptional binary containing a rapidly spinning neutron star underwent a dramatic change in behavior never before observed - the pulsar radio beacon vanished and the system…

Kepler-421b has been revealed as a transiting exoplanet with the longest known year - 704 days. For comparison, Mars orbits our Sun once every 780 days.  The farther a planet is from its star…

A new discovery that many small galaxies throughout the universe do not 'swarm' around larger ones like bees but instead 'dance' in orderly disc-shaped orbits is a challenge to our understanding of…