High up in Earth's orbit, millions of human-made objects large and small are flying at speeds of over 15,000 miles per hour.

A mysterious object the size of Galway could potentially be an aggressive alien spacecraft set to attack Earth in November, a new study suggests. Earlier this month, experts confirmed the discovery of ...

Satellite breakups and anti-satellite tests have created an alarming amount of debris, a crisis now exacerbated by the rapid expansion of commercial constellations such as SpaceX’s Starlink. The ...

The long-awaited photos, snapped by multiple NASA spacecraft between September and mid-October, show a tiny, glowing orb encircled by a hazy halo of gas and dust, hurtling through space about 190 ...

A rare visitor from outside our solar system, named 3I/ATLAS, has caught the attention of scientists worldwide. NASA recently ...

Astronomers have spotted an intriguing cluster of objects in the Kuiper belt, an enormous, donut-shaped region of icy objects ...

More accurate orbit predictions for satellites and space debris as well as a better understanding of the water masses present on Earth: Researchers at achieved both using satellite laser ranging. More ...

China routinely sends astronauts to and from its space station Tiangong. A crew capsule is about to undock from the station and return to Earth, but there's nothing routine about its journey home.

Astronomers using NASA's Chandra X-ray space telescope have witnessed a massive black hole jet slam into an unknown object in space. Astronomers have seen black hole jets blasting cosmic objects ...

Astronomers have detected an astonishing celestial object emitting bright flashes of radio waves and X-rays that last for two minutes and repeat every 44 minutes. In a fresh twist, the discovery marks ...

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights. The size of the solar system is defined by the volume ...