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Hawks
SFN Regular
Canada
1383 Posts |
 Posted - 04/25/2007 : 02:10:36
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From Bad Astronomy:
quote:
The European Southern Observatory is reporting that they have found the most Earthlike planet yet orbiting another star. It has about 1.5 times the Earth's diameter, and five times its mass. This makes it the smallest extrasolar planet yet found (two other planets have already been found orbiting that star, with 15 and 8 times Earth's mass).
Pretty cool!
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METHINKS IT IS LIKE A WEASEL
It's a small, off-duty czechoslovakian traffic warden! |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 04/25/2007 : 02:55:53 [Permalink]
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Wonder what the gravity is like on that planet? Would visitors have to train for years in a centrafuge just to be able to walk on its surface?
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
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Vegeta
Skeptic Friend
United Kingdom
238 Posts |
Posted - 04/25/2007 : 04:16:02 [Permalink]
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| so its a rocky planet? Could this also be the first non-gas giant to be found that is larger than Earth? |
What are you looking at? Haven't you ever seen a pink shirt before?
"I was asked if I would do a similar sketch but focusing on the shortcomings of Islam rather than Christianity. I said, 'No, no I wouldn't. I may be an atheist but I'm not stupid.'" - Steward Lee |
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filthy
SFN Die Hard
USA
14408 Posts |
 Posted - 04/25/2007 : 04:37:17 [Permalink]
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Kinda reminds me of a couple of Larry Nivin's short stories in Tales of Known Space.
A marvelous find indeed. I wonder when the state of the art will be able to dectect yet smaller planets, and what a pity we'll never get to visit them.
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
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Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist! 
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 04/25/2007 : 04:57:20 [Permalink]
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quote:
Originally posted by HalfMooner
Wonder what the gravity is like on that planet? Would visitors have to train for years in a centrafuge just to be able to walk on its surface?
With 1.5 times Earth's diameter and 5 times the mass, the surface gravity would be 2.222 times greater than Earth's. A 150-pound person would feel like they're lugging an extra 183 pounds around with them. Medieval armor wasn't even that heavy. |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 04/25/2007 : 05:27:43 [Permalink]
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Thanks, Dave! I just didn't have the math. It seems as though a thin, athletic person could walk around for brief periods between rests in a water bed. But woe is he who trips and falls down. A powered exoskeleton and something like an aviator's G-suit (to prevent blood pooling in the lower extremities) might help.
Of course, the conditions of the "earth-like" planet are extrapolated entirely from the wobble of the star, without direct observation. Basically, all we know for sure is that a mass of that size is orbiting at a temperate distance from the primary. The mass might even be two bodies, orbiting one another. Good extrapolation, but also room for some surprises.
If there were plant life, I'd imagine photosynthesis being carried out by an analog of chlorophyll better suited to the lower wave-length of the reddish sun.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
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Dave W.
Info Junkie
USA
26022 Posts |
Posted - 04/25/2007 : 06:41:00 [Permalink]
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quote:
Originally posted by HalfMooner
Thanks, Dave! I just didn't have the math.
Given numbers relative to Earth, you only need to divide the relative mass by the square of the relative radius. For example, the Moon is only 0.012298 times as massive as Earth, and it's only got 0.27241 times Earth's radius. 0.012298/(0.272412) is 0.012298/0.07421, or 0.166, or that famous "one-sixth Earth's gravity" we all learned in elementary school.
So, for the new planet, 5/(1.52) is 5/2.25, or 2.222… |
- Dave W. (Private Msg, EMail)
Evidently, I rock!
Why not question something for a change?
Visit Dave's Psoriasis Info, too. |
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Dude
SFN Die Hard
USA
6891 Posts |
Posted - 04/25/2007 : 09:27:09 [Permalink]
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High G environments offer some interesting challenges to human physiology. An exceptionally physically fit person could walk around for a while, not long because you'd be probably be lugging around protective gear as well. But any resting positions would need to be extremely well padded to prevent pressure ulcers, and there would be other problems with circulation with extended exposure.
If such a planet had an atmosphere it would probably be more dense than what we have here on earth also. Higher pressure gas has its own set of problems too.
Also, in higher gravity, things fall faster. So falling from 3 feet on earth doesn't present much risk of serious injury to the average astronaut, but in 2.22 gravities it would.
Isn't space travel fun? Well, its a fun mental excercise anyway.
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Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong.
-- Thomas Jefferson
"god :: the last refuge of a man with no answers and no argument." - G. Carlin
Hope, n.
The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth |
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BigPapaSmurf
SFN Die Hard
3192 Posts |
Posted - 04/25/2007 : 10:26:32 [Permalink]
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| Yeah thats why its so funny when douche-bags like Travolta say we should start moving to other planets to avoid global warming. |
"...things I have neither seen nor experienced nor heard tell of from anybody else; things, what is more, that do not in fact exist and could not ever exist at all. So my readers must not believe a word I say." -Lucian on his book True History
"...They accept such things on faith alone, without any evidence. So if a fraudulent and cunning person who knows how to take advantage of a situation comes among them, he can make himself rich in a short time." -Lucian critical of early Christians c.166 AD From his book, De Morte Peregrini |
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Dr. Mabuse
Septic Fiend
Sweden
9688 Posts |
Posted - 04/25/2007 : 14:30:00 [Permalink]
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| The Swedish news-tabloid I read reported that the planet has the right average distance to the star to have liquid water. If that is true, then the possibility for life rise dramatically. |
Dr. Mabuse - "When the going gets tough, the tough get Duct-tape..."
Dr. Mabuse whisper.mp3
"Equivocation is not just a job, for a creationist it's a way of life..." Dr. Mabuse
Support American Troops in Iraq:
Send them unarmed civilians for target practice..
Collateralmurder. |
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Cuneiformist
The Imperfectionist
USA
4955 Posts |
Posted - 04/25/2007 : 14:40:06 [Permalink]
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| But if the planet were covered largely by water, and if life there were water-based, the extra weight wouldn't be so bad, no? |
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Dude
SFN Die Hard
USA
6891 Posts |
Posted - 04/25/2007 : 15:21:07 [Permalink]
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Cune said:
quote:
But if the planet were covered largely by water, and if life there were water-based, the extra weight wouldn't be so bad, no?
I was only referring to us being in such an environment.
Any life naturally occuring on such a planet would, obviously (I think), be adapted to the higher gravity.
Land based organisms would probably be smaller, definitely stronger, and definitely faster, than what we see on our planet. In 2.22 gravities objects accelerate roughly twice as fast as they do here on earth when falling. Any organism there would be adapted to the higher speeds and increased weight.
But yeah, in an ocean environment the weight thing would not be such a big deal.
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Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong.
-- Thomas Jefferson
"god :: the last refuge of a man with no answers and no argument." - G. Carlin
Hope, n.
The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 04/25/2007 : 16:31:03 [Permalink]
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On such a planet, any atmosphere would also have a very steep pressure gradient with altitude. Any ocean would have a steep pressure gradient with depth as well. Properly suited, a visitor from earth might be able to swim about quite comfortably in the upper levels of such an ocean, buoyed by the water against the effects of the greater gravity. Fun to speculate.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
| Edited by - HalfMooner on 04/25/2007 16:32:04 |
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Dr. Mabuse
Septic Fiend
Sweden
9688 Posts |
Posted - 04/25/2007 : 19:13:14 [Permalink]
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The buoyancy depends of the weight of the displaced water, and since water in rather incompressible, they buoyancy would not differ from Earth.
(edit spelling)
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Dr. Mabuse - "When the going gets tough, the tough get Duct-tape..."
Dr. Mabuse whisper.mp3
"Equivocation is not just a job, for a creationist it's a way of life..." Dr. Mabuse
Support American Troops in Iraq:
Send them unarmed civilians for target practice..
Collateralmurder. |
| Edited by - Dr. Mabuse on 04/25/2007 19:14:59 |
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beskeptigal
SFN Die Hard
USA
3834 Posts |
Posted - 04/26/2007 : 02:51:41 [Permalink]
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quote:
Originally posted by Dr. Mabuse
The Swedish news-tabloid I read reported that the planet has the right average distance to the star to have liquid water. If that is true, then the possibility for life rise dramatically.
This was the whole point of the significance of the discovery. The temperature is right.
I'll wait till they get the spectrograph revealing the composition back before getting too excited. The real discovery here is we have found the first planet that isn't a gas giant. The fact it is orbiting a red dwarf star allowed it to be detected while only larger gas giants can wobble larger stars enough to be detected so far.
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| Edited by - beskeptigal on 04/26/2007 02:52:19 |
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beskeptigal
SFN Die Hard
USA
3834 Posts |
Posted - 04/26/2007 : 02:54:29 [Permalink]
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quote:
Originally posted by BigPapaSmurf
Yeah thats why its so funny when douche-bags like Travolta say we should start moving to other planets to avoid global warming.
Did you catch Colbert's joke on this tonight? He said, "we found an Earth-like planet, that means you can drive the Hummer without worry again", or something like that. It was funny.
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Earthlike planet
