Solar System

Webb Telescope Reveals Worlds in the Farthest Reaches of the Solar System

James Webb Space Telescope data on distant worlds confirm some solar system formation hypotheses and confuse others.

Kuiper Belt Object

Solar System

Amateur Scopes Help Find Planet Formation’s Missing Link

A surprisingly inexpensive setup of amateur equipment is helping astronomers on their quest to find Kuiper Belt objects of every size to better understand how planets formed in our solar system.

Illustration of New Horizons flying by Ultima Thule

Space Missions

Planning the New Horizons Exploration of Ultima Thule

Alan Stern, principal investigator of NASA's New Horizons mission, gives a detailed preview of what the spacecraft will be doing in the days up to, during, and after the impending flyby of the Kuiper Belt Object 2014 MU69.

Illustration of New Horizons flying past 2014 MU69

Space Missions

New Horizons On Approach to the First Exploration of a Kuiper Belt Object

Take a look behind the scenes as the New Horizons team gears up for the historic first flyby of a body in the remote Kuiper Belt, in this first of a four-part series from the mission's Principal Investigator Alan Stern.

Illustration of Planet Nine

Solar System

New Object Found in Far Outer Solar System

Astronomers have discovered a object—2015 TG387—that could help in the hunt for a hypothesized Planet Nine in the distant reaches of the solar system.

Dwarf planets compared

Solar System

Dwarf Planet 2007 OR10: Big, Dark, and Slow

A Kuiper Belt object discovered nearly a decade ago turns out to be much darker — and thus larger — than thought. It's also an especially slow spinner.