Astronomers are preparing to study a dwarf planet that last came near Earth 11,000 years ago. Sedna is moving closer to the Sun, and this has intrigued experts who are eager to learn about the distant ...

It took over nine years for New Horizons to reach Pluto after blasting off atop an Atlas 5 rocket on Jan. 19, 2006. After ...

I/ATLAS might be over 7 billion years old, a new study reports, which would make it the oldest comet known. But experts caution we need more data.