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

These pictures of Mercury’s pockmarked surface are ... some of the clearest views we’ve ever had of the Swift Planet. Read more Inside NASA’s ambitious plan to bring the ISS crashing back ...

We'll see six planets in the first part of February – Mars, Jupiter, Uranus, Neptune, Venus and Saturn – and on Feb. 28, they'll be joined by Mercury. But not all of them will be visible to ...

But of these planets, which is nearest to the sun? Mercury is a strange little world. There are some craters on its surface that never see sunlight. It also has the most extreme temperatures of ...

Like a celestial parade across the cosmos, five bright planets are lighting up the night sky and visible with the naked eye ...