CAPE CANAVERAL, Fla. (AP) – The only spacecraft ever to orbit Mercury ended its four-year tour with a crash landing Thursday. NASA’s Messenger plunged from orbit as planned and slammed into the sun’s ...

What is a planetary retrograde? And what connection does it have to astrology? We explain how planets move across the sky.

Skywatchers across the Northern Hemisphere have caught a fleeting glimpse of Mercury as it made one of its final visible appearances of the year. Appearing low on the southwestern horizon just after ...

The discovery of the fourth star was done through an algorithm called QUADCOR, which isolates the distinct spectral fingerprints of all four stars simultaneously. By detecting the individual signals, ...

(PhysOrg.com) -- MESSENGER scientists will highlight the latest results on Mercury from MESSENGER observations obtained during the first six months (the first Mercury solar day) in orbit. These ...

A collision with an asteroid might have set the planet Mercury whirling oddly in its orbit, a new study suggests. When one body orbits another — say, a moon around a planet or a planet around a star — ...

On March 25, the MESSENGER spacecraft completed its 4,000th orbit of Mercury, and the lowest point in its orbit continues to move closer to the planet than ever before. The orbital phase of the ...