Posted on 06/13/2005 12:42:00 PM PDT by The_Victor
WASHINGTON A planet that may be Earth-like but too hot for life as we know it has been discovered orbiting a nearby star.
The discovery of the planet, with an estimated radius about twice that of Earth, was announced today at the National Science Foundation.
"This is the smallest extrasolar planet yet detected and the first of a new class of rocky terrestrial planets," Paul Butler of the Carnegie Institution in Washington said in a statement. "It's like Earth's bigger cousin."
Geoffrey Marcy, professor of astronomy at the University of California, Berkeley, added: "Over 2,000 years ago, the Greek philosophers Aristotle and Epicurus argued about whether there were other Earth-like planets. Now, for the first time, we have evidence for a rocky planet around a normal star."
Though the researchers have no direct proof that the new planet is rocky, its mass means it is not a giant gas planet like Jupiter, they said. They estimated the planet's mass as 5.9 to 7.5 times that of Earth.
It is orbiting a star called Gliese 876, 15 light years from Earth, with an orbit time of just 1.94 Earth days. They estimated the surface temperature on the new planet at between 400 degrees and 750 degrees Fahrenheit.
Gliese 876 is a small, red star with about one-third the mass of the sun. The researchers said this is the smallest star around which planets have been discovered. In addition to the newly found planet the star has two large gas planets around it.
Butler said the researchers think that the most probable composition of the planet is similar to inner planets of this solar system a nickel/iron rock.
Gregory Laughlin of the Lick Observatory at the University of California, Santa Cruz, said a planet of this mass could have enough gravity to hold onto an atmosphere. "It would still be considered a rocky planet, probably with an iron core and a silicon mantle. It could even have a dense steamy water layer."
Three other extrasolar planets believed to be of rocky composition have been reported, but they orbit a pulsar the flashing corpse of an exploded star rather than a normal type of star.
On the Net:
National Science Foundation: http://www.nsf.gov
Ask a silly question....
Seeing the knowledge that gets posted to threads like this has me convinced we have lots of talent for a faculty at "Freep U"
I'm thinking our resident expert might be able to answer you on this. How 'bout it, RA?
That is SO true. Ask any question about anything (particularly science or law or [of course] politics, facts of any sort, history, the Bible, et. seq.) and you will get very erudite answers.
Post an innocent post and misspell something or use improper grammar and you will also get erudite answers!!
If I was an author, I would run my stuff by FR first for fact checking, syntax and quality.
That's a good idea- our spelling police and fact police would be doing us a favour!
Hey, do you like my tag? I changed from a more popular one because I thought this one was pretty funny ...
The planet is inhabited by SHORT LITTLE BEINGS that resemble Helen Thomas.
There is an upper mass limit for planets. It gets a little fuzzy but here is a nice page describing such:
"The term "planet" carries the connotation of a larger, relatively spherical body in a mass range at least as great as that from Mercury to Jupiter. No universally accepted definition is available. Therefore for this discussion, a planet is defined as a star-orbiting object (of no presupposed, particular mode of origin) with a mass greater than that required for the development of a near-spherical shape (roughly the mass of the asteroid Vesta) but smaller than the upper limit in mass discussed below. Planets are thus generally larger than the asteroids of our own solar system, although Ceres would qualify in this nomenclature as a very small planet."
Check out the table. :-)
http://www7.nationalacademies.org/ssb/detectionch1.html
Ah.
I understand it's a strange planet, very different from Earth ... one where they actually CONVICT pedophiles and murderers!
If the radial velocity of a star changes in a period which is consistent with an orbiting planet, then it is now being classified as having possible planet.
I am sorry, but these rapid orbits are starting to disturb me.
This may be a new discovery of rapid pulsations of variable stars, which we have not observed before. Even the Sun, as much as it has been studied, is being suspected of being a variable star. As technology advances, our new discoveries are able to identify details that have never been observed before.
For the last few years, the discovery of new planets has excited me. However, these very short orbital periods are starting to make me wonder if we are not fooling ourselves.
Please do not get me wrong. The discovery and understanding of new stellar physics, which could simulate the rapid Doppler shifts observed, would be equally important.
Today, the study of physics and astronomy is getting very exciting. New things are being discovered almost every day.
Hi! :-)
Instead of going into pages of detail here, this link should answer your question:
http://outreach.atnf.csiro.au/education/senior/astrophysics/variable_types.html
Me neither. I can see why it would be unlikely, though, at least with smaller stars like Gliese, because the chances of there being enough rocky material for a Jupiter-sized solid, probably aren't all that high. Jupiter's 318 times the mass of the earth. That's a lot of material.
So what exactly is it that makes it 'Earth-like'?
LOL seen that in a different form. Scares the cr@p out of every non-pilot I share it with.
The fact that it's made of rock. This is a problem of journalism- what a scientist would regard as earth-like (a really big chunk of rock) is not what most people would consider earth-like (where we could leave our spacesuits at home).
No, its Ceti Alpha 5......
"KAHN!!!!!!!!!!!!!!!!!!"..........
Alpha city six..........KHHHHAAAASNNNNNN!!!
"It is orbiting a star called Gliese 876, 15 light years from Earth, with an orbit time of just 1.94 Earth days."
Heh... a satellite in prograde rotation will enjoy a transfer of momentum from the rotating parent body. I guess we all know what that means. ;') And this has happened before...
Scientists Find Extrasolar Planet With Atmosphere Much Like Jupiter
by John Noble Wilford
March 13, 2003
http://www.nytimes.com/2003/03/13/science/13PLAN.html
Uh, hate to show what a geek I am, but I think you mean, "Seti Alpha V".
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