Topic: Kuiper Belt

Do Pluto's moons pose risks for NASA spacecraft? (+video)

Scientists are planning a new route for NASA's New Horizons space probe as it approaches a potentially perilous path toward Pluto. They aim to chart a safe, but interesting course.

Hubble spots fifth moon orbiting ex-planet Pluto

Scientists have announced the discovery of a fifth moon of Pluto. Dubbed P5 for now, it is the smallest moon yet detected orbiting the frigid dwarf planet.

Pluto's fifth moon: five fascinating facts (+video)

Using data from the Hubble telescope, SETI scientists spotted a fifth moon orbiting the icy dwarf planet Pluto.

Pluto now has at least five moons. Can we go back to calling it a planet?

Long considered a planet, Pluto was reclassified as a 'dwarf planet' in 2006 by the International Astronomical Union. Will the discovery of a fifth moon prompt astronomers to reconsider?

Hubble telescope spots fifth moon orbiting Pluto (+video)

Almost exactly a year after it spotted a fourth moon orbiting the icy dwarf planet, the Hubble Space Telescope has detected a fifth one.

Draconid meteor shower: Don't let daylight or nearly full moon stop you

Draconid meteor shower viewing is potentially much more exciting this year, as Earth is expected to hit some tendrils of comet dust head-on. But the peak is Saturday afternoon.

Where did Earth's water come from? Comet Hartley 2 offers new clues.

The composition of comet Hartley 2 suggests that comets might have been a bigger source of Earth's water than previously thought. It's also challenging models of solar system formation.

Pluto moon discovery hints at future surprises for NASA probe

Pluto moon: The tiny new moon — announced July 20 and called P4 for now — brings the number of known Pluto satellites to four.

End of the world May 21st? About a billion years too soon, astronomers say.

Beginning of the end of the world: May 21st is what a California minister (with a considerable following) predicts. Scientists, for their part, consider the sun's 'habitable zone' in calculating when Earth will become toast.

Should Pluto be restored as a planet? Experts weigh in.

New calculations indicate that Pluto might be the largest object in the outer solar system. Does it now deserve to be called a planet again?

New telescopes could revolutionize astronomy, but at what price?

The case for adding new ground-based telescopes is compelling, astronomy experts say. But they cost $700 million to $1 billion apiece just to build.

Kepler mission to hunt for planets just our size

The US will launch the Kepler spacecraft Friday to look for other Earths.

Comet Lulin arrives tonight - break out your telescopes

The Pluto Files

A lively account of the ‘exile’ of Pluto, everyone’s favorite ex-planet.

Across the Milky Way, more planet Earths?

Two new discoveries suggest that sunlike solar systems like ours – with life-hosting planets – are more common than previously thought.

On the horizon: News from the frontiers of science.

Comets and asteroids made of similar stuff, a bird needs more than plumage to pick a mate, and nanotech builds a better radio.