New Horizons' Data of Pluto/Charon Show Rarity of Small Kuiper Belt Objects

Pluto’s largest moon, Charon, as seen by New Horizons in 2015. The lack of smaller craters -less than expected – suggests that small objects less than a mile in size are rare in the Kuiper Belt. Photo Credit: NASA/JHUAPL/SwRI/Alex Parker

The Kuiper Belt is a vast region of rocky debris in the outer Solar […]

New 'Farewell' Images of 2014 MU69 Reveal Weird Flatter Shape

The farewell view of 2014 MU69. The KBO was illuminated along one edge by the Sun as New Horizons sped past it. The blurring is the result of the long exposure time of the camera. Photo Credit: NASA/Johns Hopkins Applied Physics Laboratory/Southwest Research Institute/National Optical Astronomy Observatory

When New Horizons sent back its first […]

New Horizons Team Successfully Observes Transit of Next KBO Target, and Clouds on Pluto!

Four members of the South African observation team, who helped to track the occultation of a star by the KBO called 2014 MU69, the next target for the New Horizons spacecraft. Photo Credit: NASA/JHUAPL/SwRI/Henry Throop

With the Pluto flyby now well behind them, the New Horizons team has been busy preparing for the […]

New Moon Discovered by Hubble Orbiting Third Largest Dwarf Planet in Kuiper Belt

Two images of dwarf planet 2007 OR10 from Hubble, taken a year apart, showing the small moon. Image Credit: NASA/ESA/C. Kiss (Konkoly Observatory)/J. Stansberry (STScI)

Moons are exceedingly common in the Solar System – Jupiter alone has 67! But smaller planets do as well of course, except for Mercury and Venus, and even […]

'Cracked and Tipped Over' Pluto Has a Subsurface Ocean: New Evidence From New Horizons

View of Sputnik Planitia on Pluto. This vast region of nitrogen ice provides clues that a subsurface ocean of liquid water exists on Pluto. Photo Credit: NASA/JHUAPL/SwRI

Pluto, a tiny frigid world in the distant outskirts of the Solar System, has been full of surprises, as first revealed by the New Horizons spacecraft […]

Does Pluto Have a Subsurface Ocean? New Research Says Probably

The discovery of huge faults on Pluto provides evidence for a possible liquid water ocean beneath the ice crust. Photo Credit: NASA/JHUAPL/SwRI

So-called “waterworlds” have been found to be surprisingly common in the Solar System—small icy moons which have ice crusts but oceans of liquid water below the surface. These include Jupiter’s moons […]

Is 'Planet 9' Really a Second Massive Kuiper Belt?

The Kuiper Belt is a massive collection of dwarf planet- and asteroid-sized worlds orbiting far past Neptune. Is the hypothetical Planet 9 really a second such belt? Image Credit: T. Pyle (SSC)/JPL-Caltech/NASA

The announcement of a possible large ninth planet in our Solar System way beyond Neptune last month caused a lot of […]