"This agreement represents a significant milestone for Planet; it is our largest contract to date and is a major step forward ...

It is believed that the planet, named HD 20794 d, is at just the right distance from its star to sustain water on its surface ...

As a result, scientists are increasingly monitoring Earth from space. NASA alone has dozens of missions dedicated to solving our planet's mysteries. At the same time, telescopes are gazing outward ...

Starting at 12:30 p.m. ET (1730 GMT) on Saturday (Jan. 25), astrophysicist Gianluca Masi of the Virtual Telescope Project ...

The night sky is putting on a celestial show with a dazzling "planetary parade" featuring six major planets and a bonus comet ...

Stargazers will be treated to a rare seven-planet alignment in February. This is what scientists hope to learn.