The boundary of the Solar System remains somewhat poorly understood. We know we are within it, in a region of space called ...

Telescopes around the world are now tracking a new visitor to our celestial neighborhood. Streaking through at a speed and trajectory that not even the Sun's immense gravity can capture, we will only ...

Scientists have been wondering for years whether there is a ninth planet in our solar system. Now, a study by Japanese scientists seems to bust that belief. They have found an object orbiting the Sun ...

Our Sun’s outer atmosphere, the corona, is millions of degrees hotter than it should be, and no one knows why.

A newly discovered object speeding through our solar system is sparking excitement among astronomers because it’s not from around here. Believed to be a comet, the object is only the third celestial ...

Our solar system’s latest and only third known interstellar visitor is becoming more fascinating by the week. Spotted in early July, the object, dubbed 3I/ATLAS, is widely believed to be a comet. It’s ...

NPR's Ari Shapiro talks with astronomer David Jewitt about what we can learn from the third interstellar object to have entered our solar system, a comet-like object known as 3I/ATLAS. A remarkable ...