A Year of Assessing Astronomical Hazards
31.12.2002

Could an asteroid destroy civilization on Earth? Mountain-sized space rocks could potentially impact the Earth causing global effects, and perhaps even be mistaken for a nuclear blast of terrestrial origin. Such large impacts are rare but have happened before. Modern telescopes have therefore begun to scan the skies for signs of approaching celestial hazards.

A Perseid Meteor
11.08.2004

The ongoing Perseid Meteor Shower should be at its strongest tonight and tomorrow night. Although meteors should be visible all night long, the best time to watch will be between 2:00 AM and dawn each night. In dark, moonless, predawn skies you may see dozens of meteors per hour.

Everest Panorama from Mars
8.12.2013

If you could stand on Mars -- what might you see? Scroll right to find out. The robotic Spirit rover that rolled around Mars from 2004 to 2009 Mars climbed...

Collapse in Hebes Chasma on Mars
12.08.2014

What's happened in Hebes Chasma on Mars? Hebes Chasma is a depression just north of the enormous Valles Marineris canyon. Since the depression is unconnected to other surface features, it is unclear where the internal material went.

APOD: 2025 January 27 Б Pleiades over Half Dome
27.01.2025

Stars come in bunches. The most famous bunch of stars on the sky is the Pleiades, a bright cluster that can be easily seen with the unaided eye. The Pleiades lies only about 450 light years away, formed about 100 million years ago, and will likely last about another 250 million years.

Apollo 12: Stereo View Near Surveyor Crater
13.07.2002

This weekend's stereo picture finds Apollo 12 astronaut Pete Conrad standing on the lunar surface near the southern rim of Surveyor Crater in November of 1969. With red/blue glasses you can gaze beyond the spacesuited Conrad across the magnificent desolation of the Moon's Ocean of Storms.

APOD: 2025 January 12 Б Mimas: Small Moon with a Big Crater
12.01.2025

Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn's smallest round moons. Analysis indicates that a slightly larger impact would have destroyed Mimas entirely.

Islands of Four Mountains from Above
22.06.2010

Our Earth is covered by volcanoes. Volcanoes are breaks in the Earth's cool surface where hot liquid rock from the interior comes out -- sometimes suddenly. In the above image from the ASTER camera...

Milky Way Over the Spanish Peaks
24.05.2016

That's not lightning, and it did not strike between those mountains. The diagonal band is actually the central band of our Milky Way Galaxy, while the twin peaks are actually called the Spanish Peaks -- but located in Colorado, USA.

Martian Moon Phobos Crosses the Sun
10.04.2019

What's that passing in front of the Sun? It looks like a moon, but it can't be Earth's Moon, because it isn't round. It's the Martian moon Phobos. The featured video was taken from the surface of Mars late last month by the Curiosity rover.