Astronomers find smaller Neptunian rocks

August 10, 2006

A Taiwan-led study suggests smaller frozen chunks of rock in the outer reaches of the Solar System can be spotted when they obscure starlight.

Nearly 1,000 trans-neptunian objects, or TNOs -- found beyond the orbit of the planet Neptune -- have been seen with conventional telescopes.

The size distribution of such frosty remnants gives astronomers important clues about the formation of the Solar System. But direct observation is only possible for TNOs larger than a few tens of miles across.

Now, astronomer Hsiang-Kuang Chang and colleagues at National Tsing Hua University in Hsinchu, Taiwan, say they've identified 58 TNOs smaller than about 325 feet across, by looking at X-rays being emitted from the star Scorpius X-1.

The scientists say as the TNOs move, they block the line of sight of NASA's orbiting telescope, the Rossi X-ray Timing Explorer, for a few milliseconds. That's long enough to identify the objects and estimate their size, the astronomers say.

The research appears in this week's issue of the journal Nature.

Copyright 2006 by United Press International

Explore further: Is there life on Pluto?

Related Stories

Is there life on Pluto?

July 13, 2015

First discovered in 1930, Pluto was considered to be the ninth planet in our Solar System for many decades. And though its status has since been downgraded to that of a dwarf planet, thanks to the discovery of Eris in 2004, ...

What is the newest planet?

July 7, 2015

With astronomers discovering new planets and other celestial objects all the time, you may be wondering what the newest planet to be discovered is. Well, that depends on your frame of reference. If we are talking about our ...

What is the Kuiper Belt?

June 17, 2015

Dr. Mike Brown is a professor of planetary astronomy at Caltech. He's best known as the man who killed Pluto, thanks to his team's discovery of Eris and other Kuiper Belt Objects. We asked him to help us explain this unusual ...

A recipe for returning Pluto to full planethood

February 20, 2015

A storm is brewing, a battle of words and a war of the worlds. The Earth is not at risk. It is mostly a civil dispute, but it has the potential to influence the path of careers. In 2014, a Harvard led debate was undertaken ...

Hubble harvests distant solar system objects

September 13, 2010

Beyond the orbit of Neptune reside countless icy rocks known as trans-Neptunian objects (TNOs). One of the biggest, Pluto, is classified as a dwarf planet. The region also supplies us with comets such as famous Comet Halley. ...

Recommended for you

Dense star clusters shown to be binary black hole factories

July 29, 2015

The coalescence of two black holes—a very violent and exotic event—is one of the most sought-after observations of modern astronomy. But, as these mergers emit no light of any kind, finding such elusive events has been ...

Image: Hubble sees a dying star's final moments

July 31, 2015

A dying star's final moments are captured in this image from the NASA/ESA Hubble Space Telescope. The death throes of this star may only last mere moments on a cosmological timescale, but this star's demise is still quite ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.