Possible Earth-like planet discovered

Houston Comical (AP) ^ | June 13, 2005, 2:14PM

[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.

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On the Net:

National Science Foundation: http://www.nsf.gov

[Rummyfan]

Is it Talos IV?????

[Junior]

I would've said "Mercury-like." Besides, this thing is hugh (I'm series).

[beltfed308]

They estimated the surface temperature on the new planet at between 400 degrees and 750 degrees Fahrenheit.

That's earth like?

[RockinRight]

They've already found sentinent life:

[cripplecreek]

Just whipping around it's sun isn't it.

[shekkian]

It is orbiting a star called Gliese 876, 15 light years from Earth, with an orbit time of just 1.94 Earth days.

Wow!! This planet's really moving.

Imagine the mortgage rates on this real estate.

[NewMediaFan]

sounds like a good place for Dean's voter-outreach program

[lilylangtree]

If we only had a Stargate!

[Steve_Seattle]

"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."

" . . . too hot for life as we know it . . . with an estimated radius about twice that of earth . . . "

Doesn't sound very "Earth-like" to me.

[The_Victor]

Wow!! This planet's really moving.

Imagine the mortgage rates on this real estate.

But you could live to be 14000 years old.

[IllumiNaughtyByNature]

Shekkian, did it say the distance from the it's sun? That orbit is haulin a$$ either way.

[in hoc signo vinces]

Exactly...how is this Earth like? Granted it is more Earth like than a gas giant, but still.

[Righty_McRight]

A planet that may be Earth-like — but too hot for life as we know it —

I claim this planet for Texas. We will hang out there during the summer.

[mnehring]

They estimated the surface temperature on the new planet at between 400 degrees and 750 degrees Fahrenheit.

Bush caused global warming there too?

[Da Bilge Troll]

I just can't believe that orbital period. It would have to be so close to the star that friction would quckly bring it down.

1.94 YEARS, maybe?

[Righty_McRight]

The left did say that environmental policies of this administration would have FAR reaching consequences.

[RockinRight]

Actually, 1.94 days is possible. The star is dim so while it's hot as the article said, it's nowhere near as hot as if the planet were the same distance from our sun.

[Graybeard58]

with an orbit time of just 1.94 Earth days.

That sucker is movin'!

[scott7278]

That's earth like?

Relatively speaking, I guess.

[The_Victor]

I just can't believe that orbital period. It would have to be so close to the star that friction would quckly bring it down.

This is a significant factor in the orbital period:

Gliese 876 is a small, red star with about one-third the mass of the sun.

[Husker8877]

Sheila Jackson-Lee (D-Mars) will be green with envy (greener).

[BenLurkin]

"They estimated the surface temperature on the new planet at between 400 degrees and 750 degrees Fahrenheit"

[Tallguy]

Yeah, but the question is who will the enviro-whacko's blame this case of Global Warming on?

[GulliverSwift]

The planet is inhabited by nerdlings.

[cripplecreek]

I'm curious if the gravity of a planet is affected by it's density. I know our gas giants aren't very dense yet they have extremely strong gravitational fields. Or is mass more of a factor than density?

[waverna]

Hope not, that whole death penalty thing and all. We could be executed for just responding to this thread!

[El Gato]

Is it Talos IV?????

No, probably Gliese 876 I, unless there's another planet closer in to it's sun.

Posting from Sol III.

[waverna]

Hot as Vulcan!

[The_Victor]

Gravitational pull is purely a function of mass and distance.

[Brett66]

It's a terrestrial planet, but it sure ain't earthlike.

[Junior]

I'm curious if the gravity of a planet is affected by it's density.

Gravity's affected by the planet's mass. Density is the mass per unit of volume, so they are related. Remember, Saturn has a density of less than 1 (the density of water) while Earth's density is 5 and some change. However, Saturn has a higher "surface" gravity than Earth because it is so much bigger.

[cripplecreek]

So a rocky planet the size of Jupiter would have the same gravitational pull as a gas giant like Jupiter?

[Junior]

No. A rocky world that size (an impossibility) would be more massive than a gas giant and have a higher surface gravity.

[in hoc signo vinces]

From the only good line in Riddick...."If I owned this place and Hell...I'd live in hell, and rent this place out."

[The_Victor]

So a rocky planet the size of Jupiter would have the same gravitational pull as a gas giant like Jupiter?

No. A rocky planet would have much greater mass that a gas planet of the same size.

[El Gato]

I'm curious if the gravity of a planet is affected by it's density. I know our gas giants aren't very dense yet they have extremely strong gravitational fields. Or is mass more of a factor than density?

The gravity field is dependent only on the mass. However the surface gravity is dependent on both the mass and the radius of the planet. The less dense planet will have a larger radius, by the cube root of the density ratio. It's surface gravity will be lower by the square of the cube root of the density ratio.

[Squawk 8888]

Doesn't sound very "Earth-like" to me.

By their standards it's almost a carbon copy. If it's solid, has an atmosphere and isn't hot enough to melt most metals it's pretty close. I blame bad reporting for the impressing they convey, because to a layman "earth like" means survivable without a spacesuit and the closest thing we have to that is Mars.

[brownsfan]

Gravity is directly proportional to mass. Density has nothing to do with the equation. Gas giants have high gravity because even though they aren't dense, there's a lot of mass involved.

[Squawk 8888]

Pretty damn close I'd say. It must be a very small star because any planet orbiting the sun that quick would melt in a matter of minutes.

[ArGee]

A planet that may be Earth-like — but too hot for life as we know it — has been discovered orbiting a nearby star.

Further investigations demonstrate that the planet is a remarkable parallel to earth. It also developed a human-like life form and developed politics similar to the United States. Unfortunately, on that planet, socialists gained the upper hand and drove all business into the ground. The people of the planet had to continue burning trees and cow dung, which lead to the state we find the planet in today.

Shalom.

[mikrofon]

between 400 degrees and 750 degrees Fahrenheit

Rampant book-burning and corresponding anti-environmental policies likely led to the conditions there...

[Squawk 8888]

I'm curious if the gravity of a planet is affected by it's density

The short answer is yes. Gravity is a function of the mass of the body and the distance from the centre of mass. Therefore the surface of a less dense planet would be further from the centre of mass and gravity at the surface would therefore be lower.

[IllumiNaughtyByNature]

Sounds right. I'd like to know more about it.

[Squawk 8888]

Actually, I don't have the math handy but I believe that a body with the density of rock and the volume of Jupiter would probably be a star, ignited by the pressure of all that mass. That's why rocky planets are small and the only large planets are the gas giants.

[Irish_Thatcherite]

They estimated the surface temperature on the new planet at between 400 degrees and 750 degrees Fahrenheit.

*************************************************************

That's earth like?

Perhaps they should have said: 'Venus like' - but that wouldn't have made an eye catching headline.

[Irish_Thatcherite]

Moore's a sentinent lifeform?

[cripplecreek]

Ive been digesting this. It's all interesting to me.

[RockinRight]

Actually, no, just a blob of tissue...like a jellyfish.