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Astronomers Claim Discovery of Earth-like Planet
Raver32 writes "A team of astronomers announced they have discovered the smallest and potentially most Earth-like extrasolar planet yet. Five times as massive as Earth, it orbits a relatively cool star at a distance that would provide earthly temperatures as well, signaling the possibility of liquid water. 'The separation between the planet and its star is just right for having liquid water at its surface,' says astronomer and team spokesperson Stephane Udry of the Observatory of Geneva in Versoix, Switzerland. 'That's why we are a bit excited.' But researchers do not yet know if the planet contains water, if it is truly rocky like Earth, which might make it hospitable to life as we know it, or whether it is blanketed by a thick atmosphere. 'What we have,' Udry says, 'is the minimum mass of the planet and its separation" from its star.'"
It may be earthlike, but it sure wouldn't be a comfortable place to spend any amount of time.
If libertarians are so opposed to effective government, why don't they all move to Somalia?
Fire off a bunch of rockets filled with Prisoners.
Call it the S.S. Botany Bay, and give them a radio to let us know how it all works out for them.
TFA is dated 24 April, 2007 -- I'm pretty sure that this is old news.
I wonder how long before we can verify an earth like extrasolar planet?
As more of these are found we may be able to plug more data into drake's equation
From the blurb itself, it's five time the size of earth, it's revolving around a cooler sun than earth, and it might not have liquid water or a thick atmosphere. Yeah, that's exactly like earth!
If someone says he and his monkey have nothing to hide, they almost certainly do.
Mass alone says very little about the surface gravity of a planet - you need to know the radius of the object to make any statement about its surface gravity. Earth's moon has slightly over a percent of the mass of Earth, but about 1/6g surface gravity. Mars has only about 10% of the mass of Earth, while having 1/3g surface gravity.
No. While it is hard to measure, gravity drops off with any altitude at all. The gravity you feel standing on top of Mt. Everest is ever so slightly less than that in Death Valley.
Andy
... they really don't know jack squat about this planet and they're just making wild speculations about it given the extremely tiny amount of gravitational aberration data that they've managed to collect with their instruments, which only really suggests anyway that there *might* be a planet of some certain mass and orbital radius there, if their instruments' measurement errors or perhaps some other gravitional phenominon aren't what they actually seeing anyway.
You're probably thinking of the shell theorem, which says that a uniform sphere of mass is gravitationally equivalent to a point mass located at the center of the sphere. This theorem does imply that a larger radius = less gravity at the surface.
Visit the
Invade!
--- What?
you can move there.
To calculate the gravitational effect of a massive sphere, its whole mass can be
:-)
considered accumulated in its center as long as you are outside of it.
So the gravitational acceleration indeed only depends on mass an distance.
Mathematical fact.
Neat additional trivia:
- Inside a hollow sphere, there is no gravitational effect by the sphere's mass - it cancels out exactly.
That's why
- Inside a massive sphere, gravitational acceleration increses linearly with the radial distance to the center.
(the mass increases with r^3 as you get further out, its effect decreases by 1/r^2 - and as it can be considered
concentrated in the middle, you get an increase by a factor of r^3/r^2 = r
Gravity is fun
All this of course only for constant density.
That's only if the radius from the centre of the objects is the same. Remember, gravity decreases as a function of the square of the distance.
Isn't the case, that, at least while you are on the planet, the math works out such that the gravity is consistent at whatever point you are on?
No, we can even measure how surface gravity varies from g=9.78 m/s2 to g=9.82 m/s2 when moving from the equator towards a pole. And this is because Earth is not perfectly round, the people at higher latitudes are closer to the center of Earth and fall faster.
They could have stated that it's the most Pluto-like extra-solar planet discovered, and been just as right. Just because it is a slightly closer match doesn't mean much. It is still not Earth-like enough to matter.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
5 times the mass means 5 times the gravity assuming the same volume.
If we assume this planet is truly "earth-like" and has similar density, then it is not a true statement that it will have 5 times the gravity of earth. If the density is similar to that of Earth, then the size of the planet will be larger. The radius will be larger by a factor of the cube root of 5 (the real one, that is), which is about 1.7, which is also almost exactly the square root of 3.
Since gravity is proportional to the inverse of the radius squared, the gravity of this planet at its surface is 1/3 the magnitude it would have if the volume were the same as Earth's.
Comparing, this means that this planet will have 5/3 the gravity of earth, or 1.67 times. 1 kg of mass would weigh about 3.68 lbs, so my meager 75kg frame would weigh 276 Earth lbs. Wouldn't be the first time...
That's kind of important, I would think.
Let me be the first to say, Hail to our alien overlords!
``No, we can even measure how surface gravity varies from g=9.78 m/s2 to g=9.82 m/s2 when moving from the equator towards a pole. And this is because Earth is not perfectly round, the people at higher latitudes are closer to the center of Earth and fall faster.''
No, that's because they drink more alcohol there.
Please correct me if I got my facts wrong.
Give each member of the team of astronomers a Steakhouse burger from BK!
So this article is telling me that an earth-like planet, only more massive, is out there circling a red star? So if a being from that world came to our planet with a yellow sun.....
with seemingly super strength.........
awesome.
Unless they have insurance salesmen, garage door openers and Fanta, I'd be hesitant to call it Earth-like. Hacks.
AND moaning on /. will affect the price of a gallon of gasoline and your ability to have a phone free of being wired tapped HOW?
Maybe you should, you know, take some action yourself of instead of whining that nobody else is.
Maybe the gravity is or isn't 5 X earth's due to altitude but I'm guessing it's significantly higher. If complex lifeforms can exist in such a heavy environment they would probably be tougher than the average human. Gilese 581 is a red-dwarf thus most of it's light is in the near-infrared. So... a lifeform with eyes would probably see infrared. So... I'm picturing an alien badass w/ nightvision... sound familiar?
I'm not fat, im just from a higher latitude :(
... and no one lives there, does it have hospitable conditions ?
Captain Kirk found a new Earth-like planet almost every week. What was even more amazing was they were occupied by PEOPLE with 1960s haircuts and clothing.
How many "Earth-like" planets are we going to hear about that may or may not truly be Earth-like in the end? We don't know if it's rocky, we don't know if it has water, we don't know if it's a lump of chode floating about in space. Seriously, let us know when you've -confirmed- something. Asshats.
that's a leap... the whole 'goldilocks' zone concept is fuzzy at best... an indicator, but not enough in itself; Take earth for example... we're NOT close enough to the sun to have liquid water by default. If the mantle cooled enough to end vulcanism, the atmosphere would grow thin, cold, and what water didn't freeze to the surface would seep down beneath the crust forever. Then take Europa... way way way too far from the sun for liquid water... and yet, due to internal stress, liquid water is not unlikely to be found there, under its crust of ice... the attributes of the body have as much if not more influence than the sun does (outside of being so close that the surface is thoroughly scorched, that is.)
I think that in planetary terms we can safely assume 5x mass will create an environment of roughly 5g ... maybe give or take 20%.
How do you justify that remark? Mars has a mass 1/9 of Earth's but a surface gravity over 1/3 of Earth's. Mercury has a mass 1/18 that of Earth but has gravity slightly higher than that of Mars.
There's just no way you can have confidence within 20% that the gravity will be proportional to the mass.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
There are two press releases that I really really wish I could take a vacation from. First, announcement of an "earth-like planet" that, when you read the details, isn't actually earthlike. Second, announcement of a "breakthrough in solar cell technology" that, when you read the details, is a piece of fundamental research that may be interesting in a scientific way but the researchers have never actually produced a working solar cell.
http://www.geoffreylandis.com
When it comes to planets, it is better to be overweight. If the planet is too small, it might not be able to maintain its atmosphere and any life would die. Having higher gravity will put a handicap on the size of terrestrial life, but aquatic life would survive just fine.
Its 20 light years away, which if you could get a probe up to say .5 c could be done in 40 years. Thats sounds like a long time until you realize Voyager probes have been in space for about 30 years.
... but right now it's kinda like being a man dying of thirst on a boat in the middle of the ocean ("water, water everywhere, and not a drop to drink").
Wake me up when we can actually swing by one of these places for a visit.
Insisting on "correct" English is like saying that there is only one, definitive recipe for chili.
5x weight = cubic root of 5 times the diameter of earth, so gravity= earth gravity times 5 divided by (cubic root of 5 squared)= 5 to the power of (1-2/3) = third root of 5 = 1.71 Earth gravity.
This means any inhabitants might look somewhat dwarf-like and will consider us as cone-heads, but isn't quite as bad as 5x.
Hey don't blame me, IANAB
You are well on your way to inventing the calculus. It is mentioned elsewhere, but when you integrate over a shell, the gravitational attraction is the same as if the shell were a point mass at the center of the shell.
Are these the guys eating the steakhouse burgers? "You either find a planet capable of supporting life or you don't. Assisted pffft"
"Call it the S.S. Botany Bay"
KHAAAAAAAAAAAAAANNNNNNNN!!!!!
(stupid slashdot caps nazis)
but does it have oil ?
kthx
Bush
Assuming that the density is a little bit less than the Earth (more like the Moon or Mars) and this "Super Earth" is thus larger by a sizable fraction..... what is the geological environment of a planet such as this like?
Since the interior heat of this planet has less surface area in proportion to its volume, internal heat from its formation and nuclear decay from heavy elements (like Uranium) would therefore cause a much larger interior heat sink... and causing substantially more techtonic activity and a great many more volcanoes.
Using Mars as a comparator here as well, Mars is smaller than the Earth, and geologically dead, with fewer but much larger volcanoes. Is it reasonable to assume this planet... if it had a rocky "surface", would literally be littered with smaller volcanoes over nearly all of its surface with much smaller "continents"?
Assume that the age of this planet is roughly similar to that of the Earth and that heavy metals (heavier than Iron) in its formation are roughly proportional to what we find on the Earth.
I just don't find that this would be all that pleasant of a place to be at, and the nearly constant volcanism would IMHO kill off nearly any attempt to colonize this planet with life.
It certainly would be a weird planet to look at though.
Actually, if I remember correctly, an object weighs less at the equator because the earth is rotating. An object in motion will travel in a straight line unless acted on by an outside force. Therefore, at the equator, gravity also acts as a centripetal force to keep the object from flying off into space. If the object is near the poles, less centripetal force is required to keep it from flying away and it is held tighter to the surface.
Is it not possible, now that we know where is, to point a big-ass telescope at it and take a look to see if we can see us some cities?
Random rants about technology: http://technorants.blogspot.com
We'll work out the details en-route. :)
To the many, many people who've taken the time to correct my shitty assumption, berate me, mod me down, and otherwise point out that in my rush to post I forgot to turn my brain on ... I hang my head in shame. I will now seek out my grade 10 physics teacher (or locate his grave as the case may be) and confess my sins.
And of course, for the angriest among you, this post presents another opportunity to mod me down.
If libertarians are so opposed to effective government, why don't they all move to Somalia?
The latest results of Messenger's first flyby of Mercury confirms a magnetic field and molten outer core. Conversely, Venus which is Earth's twin in size, seems a lot more dead. A more important factor may have been chemical composition at the time of formation - Mercury had more metal. Elements may have been unevenly distributed as function of distance from the Sun in the original planetary nebula.
"Captain, we detected an M class planet on your long range sensors."
Sorry, folks... I'm an uncurable Star Trek fan.
So say we all
Cant make a joke anymore in Slashdot :-(
20.5 light years according to my calculations =
186,000 * 60 * 24 * 365 * 20.5 =
2,004,112,800,000
that's 2 trillion+ miles to you and me.
Construction of B-Ark commences.
"Kill 'em all and let Root sort 'em out"
...that I'm "very Brad Pitt-like" in my online dating profile, even if I'm actually "five times as massive?"
I mean, otherwise we are VERY, VERY, VERY, similar, right down to the molecular level!
Any technology distinguishable from magic is insufficiently advanced.
Now, if only I knew if you meant server as in slave or serve as in food...
"Die endgueltige Teilung Deutschlands - das ist unser Auftrag." - Chlodwig Poth
...are precisely right for maintaining approximately a pint of beer in liquid condition ready to drink. Alas, having the right conditions does not a pint of beer make.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
So that article was published in 07 good catch by all you rocket scientists. :-p
2001+14-9+1=2007 == last year's news.
I think they mean L.A! Strangely Earth-like but not *quite* the same somehow...
... what about women?
... before you are ready to leave?
I am greatly saddened by the fact that the nearby Batman posting got more than 4 times as many comments as this one.
Where have all the real people gone?
If we could just find out if there are any Native American Indians on that "new" planet for us to parent we would suddenly find plenty of monies to get there and take it from them. And realistically if they could transpose some pictures of teepees arranged around in a community that uhm looks like they're intelligent, that would really set a fire under some white people's uhm you know.
Industrial Age 2 + How-to Stop Malignant Cancers.
Yup, at 1.7X earth gravity my meager 205lb weight would be a 349 lb.
The other problem is that you suddenly have to deal with 1.7x the hydrostatic pressure difference, meaning that your heart would have to pump as if you were 1.7x as tall, and other means of distributing fluids in your system (e.g. the lymphatic system) might not work as intended, either.
Reading this as an email digest, I thought,
What? Astronomers claim discovery of Earth?
Isn't that a bit cheeky?
Still, (I thought) if Columbus could claim to have discovered America (despite the little fact that there were already people living there, who presumably already knew that it existed), then perhaps the Hubble telescope guys are entitled to swing it around so it points straight down and say, Look! A life-supporting planet! And it's really close!
But then I read the actual article and it wasn't nearly so funny. :(
Eric Baird