Astronomically speaking, the fall season comes to the Northern Hemisphere on Tuesday, September 23, 2014 at 02:29 UTC (Monday, September 22 at 10:29 p.m. EDT). At that moment, the Sun passes over the Earth’s equator heading south; this event is called the autumnal equinox.
On September 21st, after a 33-minute-long rocket firing, NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft slipped into orbit around the Red Planet.
Astronomers have detected a supermassive black hole in the center of a tiny galaxy — where it has no right to be.
NASA’s Night Sky Network is conducting a new survey in order to better help the amateur astronomy community.
European space officials have decided to drop their Philae lander on November 11th onto the small end of the already-active Comet 67P/Churyumov–Gerasimenko. Success is hardly assured.
Now two years into its exploration of Mars, NASA's big rover has reached the base of the huge mound that scientists hope will reveal the Red Planet's history.
On Wednesday, a powerful X-class flare ripped through the Sun's lower atmosphere and sent a blast wave directly toward Earth that should arrive Friday and produce moderate-to-strong auroras over the weekend.
A new diagram might link the diverse visible-light characteristics of quasars to two physical properties — essentially, their accretion rate and orientation. If the analysis holds up, it could point the way toward a long-sought unification.
Get acquainted with SS Cygni, the sky's brightest cataclysmic variable star. It's guaranteed to keep you on your toes.
The Subaru Telescope has donned a new pair of glasses called Raven, a multi-object adaptive optics system that enables astronomers to correct for atmospheric turbulence over an unprecedented field of view.
International Observe the Moon Night is an event that encourages people to "look up" and enjoy our nearest neighbor. This year's InOMN is Saturday, September 6th. Here's a quiz: What astronomical object looks amazing no matter what the magnification, never looks exactly the same no matter how often you view it, and can be...
Astronomers have mapped the cosmic watershed and discovered a massive supercluster that extends more than 500 million light-years and contains 100,000 large galaxies. The Milky Way sits on the edge of this humongous structure.
Watch as the moon Rhea steals a star from the sky for nearly a minute on September 12th.
A new analysis suggests that hot super-Earths might be the skeletal remnants of hot Jupiters stripped of their atmospheres.
The astronomical calendar says autumn arrives on September 22nd. It's a season of transition, with plenty of celestial comings and goings in the evening sky. September’s equinox takes place on the 22nd at 10:29 p.m. Eastern Daylight Time. At that moment the Sun shines directly overhead as seen from the equator. Days and nights...
Astronomers are tracking down the seeds that likely grew to become today’s most massive elliptical galaxies.
A new measurement, made using radio interferometry, argues that the distance to the Pleiades star cluster measured by ESA's Hipparcos satellite really is wrong — and that ground-based astronomers had it right all along.
With a subtle beauty all its own, the earthshine we see glowing in the lunar night invites us to consider Earth's many connections to the Moon.
On August 25, 1989, a NASA spacecraft made its fourth and final planetary encounter. What it revealed 25 years ago about the Neptunian system is still amazing and still profound.
A new measurement could be the farthest back in time astronomers have ever reached when measuring a black hole’s spin.
Astronomers might have found a star that was infected by the explosive death of one of the universe’s first stars.
Seize the moment and bookend your next clear night with two fine telescopic comets: Jacques at dusk and Oukaimeden at dawn.
New data shed light on last month’s exciting discovery of a black hole triplet — but they suggest instead that the threesome is really just a twosome.
Mission planners have devised an unusual strategy for protecting orbiting spacecraft when Comet Siding Spring passes the Red Planet in October 2014.
Celebrate the anniversary of a revolutionary discovery by gathering with other astronomers to observe planetary nebulae in August's evening sky.