Perihelion is the point at which an orbiting body is closest to the sun. The word comes from Greek and literally means around ...

Astronomers have revealed new research showing that millions of new solar system objects are likely to be detected by a brand-new facility, which is expected to come online later this year.

The upcoming year will offer a blood-red moon, spectacular meteor showers and the first glimpse of the sun’s corona since ...

An artist's illustration of the view from a Kuiper Belt object. (CREDIT: NASA, ESA, and G. Bacon (STScI)) Astronomers at Princeton University have uncovered evidence that the outer solar system is ...

The giant planets weren't always where we find them today. Jupiter, Saturn, Uranus and Neptune formed in a more compact configuration and later underwent a violent reshuffling that scattered them to ...

Nothing manmade has reached further from Earth than the Voyager series of spacecraft. Hurtling away from the sun at 38,000 miles an hour, the duo have now traveled over 12 billion miles, with Voyager ...

Astronomers have spotted an intriguing cluster of objects in the Kuiper belt, the enormous, donut-shaped region of icy objects beyond the orbit of Neptune. This latest “inner kernel” was identified by ...

The Kuiper belt, a disc of icy rocks on the outermost edges of the solar system, seems to have more structure than we thought. In 2011, researchers found a cluster of objects there on similar orbits ...

Voyager 1, launched in 1977, has traveled farther than any spacecraft in human history. After more than four decades of silent endurance through space, it now sails beyond the orbit of the outer ...

The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have dubbed ...

Portal’s heat exchanger thruster, known as Flare, fires up during a test in a vacuum chamber. (Portal Space Systems Photo) Bothell, Wash.-based Portal Space Systems says it has successfully tested its ...

Somewhere at the edge of the solar system a new Earth-sized world might be lurking, dubbed Planet Y. Astronomers have long proposed that there might be hidden planets beyond the Kuiper belt, a region ...