Stargazers will be treated to a dazzling six-planet "alignment" this January.

Emily Simpson has loved space since she was a 10-year-old kid celebrating her birthday at a planetarium. Now a recent Florida ...

The northern plains of Mars, marked by thousands of mounds and hills, hold significant evidence of the planet's watery past.

Earth and Mars ... mass planet. Without Jupiter (and its migration), Mars may well have been the size of Venus and earth, or even bigger, Kane said. The low-mass Main Asteroid Belt model in ...