The Grail-A spacecraft is orbiting the moon, and its twin Grail-B has joined it today.

From New Year's moon mission to a supernova space oddity. vote for your top space story of the week.

As a new year begins, check out the most amazing space photos of the last seven days.

NASA's twin Grail gravity-mapping probes

The Grail-A spacecraft was captured by the moon's gravity on Saturday afternoon.

Take a look at the five top videos for SPACE.com readers in 2011.

Take a look at the ups and down of space exploration in 2011.

NASA's Grail mission will map the moon's gravity like never before.

It takes many years for these giants to melt.

In January 2012, skywatchers can witness a double satellite transit on Jupiter, and the peak of one of the year's best meteor showers.

Hackers seek an "uncensorable Internet in space."

Six residents of the International Space Station will celebrate the New Year from space.

These are some of the last photos of inside Atlantis you'll ever see.

The marooned Mars spacecraft is expected to fall to Earth in mid-January.

The 2012 winter solstice will not bring about destruction of the planet, scientists say.

Rex Walheim and his brother will ride one of the floats in the 2012 Tournament of Roses parade.

Microbes can survive in frigid lava tubes on Earth — and perhaps Mars as well, scientists say.

Venus crosses the sun, meteor showers galore and more grace the sky in 2012.

The Grail spacecraft will start orbiting Earth's nearest neighbor on New Year's Eve and Day.

Researchers headed to Chile to test technologies for a possible mission to Saturn's moon Titan.