New Planet Found: Icy Super-Earth Dominates Distant Solar System

[Algorem]

http://www.spaceref.com/news/viewpr.html?pid=19246

PRESS RELEASE
Date Released: Monday, March 13, 2006
Source: Ohio State University

COLUMBUS, Ohio -- An international collaboration of astronomers has discovered a "super-Earth" orbiting in the cold outer regions of a distant solar system about 9,000 light-years away. The planet weighs 13 times as much as Earth, and at -330 degrees Fahrenheit, it's one of the coldest planets ever discovered outside our solar system.

Andrew Gould, leader of the MicroFUN collaboration and professor of astronomy at Ohio State University, pointed to two key implications of the discovery. "First," Gould said, "this icy super-Earth dominates the region around its star that in our solar system is populated by the gas-giant planets, Jupiter and Saturn. We've never seen a system like this before, because we've never had the means to find them."

"And second," he added, "these icy super-Earths are pretty common. Roughly 35 percent of all stars have them."

The astronomers have submitted a paper on the planet to Astrophysical Journal Letters, and posted a copy on the Internet preprint server arXiv.org (http://arxiv.org/abs/astro-ph/0603276)...



http://www.spaceref.com/news/viewpr.html?pid=19245

Super-Earths May Be Three Times More Common Than Jupiters

PRESS RELEASE
Date Released: Monday, March 13, 2006
Source: Harvard-Smithsonian Center for Astrophysics


Cambridge, MA - Astronomers have discovered a new "super-Earth" orbiting a red dwarf star located about 9,000 light-years away. This newfound world weighs about 13 times the mass of the Earth and is probably a mixture of rock and ice, with a diameter several times that of Earth. It orbits its star at about the distance of the asteroid belt in our solar system, 250 million miles out. Its distant location chills it to -330 degrees Fahrenheit, suggesting that although this world is similar in structure to the Earth, it is too cold for liquid water or life.

Orbiting almost as far out as Jupiter does in our solar system, this "super-Earth" likely never accumulated enough gas to grow to giant proportions. Instead, the disk of material from which it formed dissipated, starving it of the raw materials it needed to thrive.

"This is a solar system that ran out of gas," says Harvard astronomer Scott Gaudi of the Harvard-Smithsonian Center for Astrophysics (CfA), a member of the MicroFUN collaboration that spotted the planet.

The discovery is being reported today in a paper posted online at http://arxiv.org/abs/astro-ph/0603276 and submitted to The Astrophysical Journal Letters for publication...

[mom cat]

1. I think we should name it Babs or Dick ... any other suggestions?

[htuttle]

2. If I'm understanding the second article correctly

Does that mean that they are suggesting that Jupiter might have a rocky core, too? That gas giants start with these "icy super-earth's" which gas then accumulates around?

For some reason, I always assumed gas giants had some more rarified cores, like liquid nitrogen, etc...

[tridim]

3. Arthur Clarke thinks they have solid diamond cores

(compressed carbon) But that was in the 70's, he might have changed his mind.

[Odin2005]

4. Gas giants are though to have cores made up of rock and "ices".

The cores form first by the collision and absorbtion of icy protoplanets into a body of about 10 eath masses. Once this body is massive enough, it starts to capture gas from the proto-planetary disc and keeps on growing untill the initiation of fusion in the system's star blows away the remaining free gas. the more distant cores take longer to get large, which is why Ice Giants like Uranus and Neptune didn't get a lot of gas and are therefore much smaller than Jupiter and Saturn. The cores of Jupiter and Saturn are extremely hot, but the pressure is so great that the water, amonia, etc. are though to be in the solid state. When the Gas giants form they throw the rest of the icy protoplanets near them out to form the Oort cloud of comets.