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Potentially Habitable Planet Discovered
- spicyj 16y agoDiscussion: http://news.ycombinator.com/item?id=1741330 http://news.ycombinator.com/item?id=1741330
- hartror 16y agoAnd indepth analysis and reality checks by Phil Plait http://blogs.discovermagazine.com/badastronomy/2010/09/29/possible-earthlike-planet-found-in-the-goldilocks-zone-of-a-nearby-star/ http://blogs.discovermagazine.com/badastronomy/2010/09/29/po...
- Devilboy 16y agoAnd on the other end of the journalistic quality spectrum, News.com.au has this article http://www.news.com.au/technology/perpetual-twilight-of-red-dwarf-planet-gliese-581g-may-host-band-of-life/story-e6frfro0-1225932102533 http://www.news.com.au/technology/perpetual-twilight-of-red-... The link from the main page reads: Odds of life on new planet '100 per cent'
- hartror 16y agoOdds of tabloid misquoting a scientist to sell more copy "100 per cent.
- hugh3 16y agoIt seems to be an accurate quote from Vogt: During a press briefing, Prof Steven Vogt told The Daily Telegraph, “Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say, my own personal feeling is that the chances of life on this planet are 100 percent.” which sounds rather excessive to me.
- zeteo 16y agoThis all seems dependent on the planet being tidally locked. How do they know that? Does a certain distance from the sun absolutely guarantee it?
- robryan 16y agoCertain tidal force being exerted I think, it would be a combination of distance and the mass of the star.
- zeteo 16y agoThat doesn't say much. How can you know for sure that such a planet will be tidally locked? At low orbital radii, you even get relativistic effects: http://en.wikipedia.org/wiki/Tests_of_general_relativity#Perihelion_precession_of_Mercury http://en.wikipedia.org/wiki/Tests_of_general_relativity#Per...
- rflrob 16y agoFrom the paper on arXiv.org: "planets that show significant eccentricities – possibly like GL 581 d – are unlikely to become locked in a 1:1-resonance. Therefore, GL 581 d is not considered to rotate synchronously in this study." I'm actually disappointed in the reporter here... that took me all of 30 seconds to find in the original paper. --see edit Following up on some of the references, it does seem like the long-standing belief is that being a certain distance from the parent star strongly predisposes a planet to tidal locking: "planets close enough to their parent star to possess liquid water on their surfaces (the conventional HZ, below) should be tidally locked (Dole, 1964)," (Scalo et al, 2007); "For stellar masses below 0.6 MSun, exoplanets orbiting in the HZ become tidally locked within the first billion years (e.g., Kasting et al., 1993; Grießmeier et al., 2004, 2005)." (Lammer et al, 2007). EDIT: D'oh! The OP is talking about 581 g, not d. Serves me right to just grab the first article I see on arXiv about a planet in the Gliese 581 system.
- hugh3 16y agoCheck out the equation towards the bottom of http://en.wikipedia.org/wiki/Tidal_locking http://en.wikipedia.org/wiki/Tidal_locking which gives a timescale for how long it takes for a body to become tidally locked to the body it orbits. I haven't plugged in the numbers for this planet, but I'm gonna assume it winds up being much shorter than the age of the star.
- robryan 16y agoIt's still a bit of a stretch to describe this as habitable in our sense of habitable here on earth. I prefer the phase most earthlike planet. Which in this case is still a fair way off being very similar, as usually there is always the conflict between the scientists that advise caution because of the unknowns in there findings compared to the media which at times skim the first few pages and sensationalize it all. Will be very interesting to see the results from Kepler in a few years in relation to finding a planet in a similar period at a similar distance to our position in the solar system.
- Garbage 16y agoThis might be nth time I am hearing a news "Potentially Habitable Planet Discovered". Nothing happens after that.
- reitzensteinm 16y agoTo be fair, that's not limited to astronomy, or even science - the vast majority of all news stories result in 'nothing happens'.
- rgrieselhuber 16y agoIt's not really actionable information at this point.
- anateus 16y agoReally? This is the first time I'm hearing that. I've seen "planet discovered" a bunch of times, with a crescendo of excitement. I was always disappointed that they were almost exclusively super-giants and the "so what" line always said something like "and if this super-giant has moons, they could be habitable!" This is the first time I've seen a story about an actual earth-like (with fairly loose parameters) planet that is roughly in the life-zone! Usually headlines that say "earth-like planet discovered!" involve either a frozen rock orbiting way outside of its sun, or a burning pebble right next to it. However important this particular planet is, I think it's a first as far as fairly plausible life candidates go. Here's to more!
- cryptoz 16y agoMost of what happens should be in your mind, your thoughts. This planet should be something you think about. Discoveries like this change our understanding of what our galaxy is like, of the prospects of other life out there, and of who we are here on Earth. Hundreds of planets like Gliese 581g will probably be found in the next three years. As we slowly build more and bigger telescopes, we'll gain more and more information about them. This is a process that takes decades. So don't expect "something to happen" tomorrow because of this discovery. Something should happen in your mind immediately, but the real and physical repercussions of this discovery are slow and expensive. If you want them to speed up, you should lobby your government to increase their funding, or perhaps donate to some of these projects yourself :)
- rblion 16y ago"we’ve almost totally depleted this planet, we can just go to this one that is 21 light-years away."
- jboss2 16y agoVery good - http://xnxx.com/ http://xnxx.com/
- dbrannan 16y agoFeel free to correct my math =================================== Voyager 2 (man's fastest space craft) is traveling 35,000 miles per hour / 60 = 583 miles per second. 187,000 miles per second equals the speed of light. Light can travel 57,395,520,000,000 miles in one year (roughly 5.7 trillion miles). So, in 21 years that would equal 57,395,520,000,000 miles x 21 years, or roughly 120 trillion miles. Thus, if Voyager 2 was our space craft we'd have 583 miles per second x 60 seconds x 60 minutes x 24 hours x 365 days x 21 years to get 386,095,248,000 billion miles towards our new planet. There is a huge gap between 386 billion and 120 trillion miles, like 311 times. That means it would take us roughly 310 x 21 years = 6528 years to get there using current technology. I just don't see us going there as being very practical.
- sliverstorm 16y agoI think the point is that it exists. We can work on getting there once we figure out whether it exists or not; no point in working on the travel part if we aren't sure the destination exists.
- inerte 16y agoIf you were born 200 years ago, you would say us being there was impossible. In a couple centuries, (hopefully) it'll be a non-issue. Who knows? The important thing is that we actually found something only theory foresee. Assuming this particular news really did it, because I'm certain I've read similar headlines in the past.
- param 16y agoLet me correct your math - there are 3600 seconds in an hour, so the Voyager is actually going <10 miles/sec
- jws 16y agoIt is also more direct to calculate Voyager's speed as a fraction of the speed of light and then divide that into the 21 light years. Voyager goes 35,000 miles per hour (given) ... 10 miles per second Light goes 187,000 miles per second (given) Voyager goes 1/2000 the speed of light Light takes 21 years to get there (given) Voyager takes 42,000 years to get there. Hopefully I didn't drop too many zeros or use the wrong reciprocal too many (non-canceling) times. But Voyager was not intended to go fast by interstellar speeds. It just needed to get to all of its planets before its electronics died. Any speed beyond that was a waste and could have been traded off against more data gathering equipment. When it comes time to send the nanobots with the directions to fabricate exploration gear and giant space arrays to transmit back the results to us, I'm sure we can make them go faster.
- skbohra123 16y agoGiven the options, I would still prefer earth.
- ck2 16y agoNow we have somewhere to go when that asteroid hits in 2098 http://blogs.discovermagazine.com/badastronomy/2010/09/28/the-newest-tiny-threat-to-earth-2010-st3/ http://blogs.discovermagazine.com/badastronomy/2010/09/28/th...
- iuguy 16y agoBear in mind that this planet is supposed to be in the habitable zone. There are three known planets within the solar system's habitable zone - Venus, Earth and Mars. Only one of them has any confirmed life.
- olefoo 16y agoAnd coincidentally the only planet in our solar system's habitable zone that supports life is the one with a largish moon.
- 8ren 16y agoOur Moon is also in the Goldilocks zone, and rocky. But it lacks an atmosphere. Is this because the Moon is small, and some threshold of gravity is required? Or somehow related to the Moon's cold and inert interior, thus no gaseous volcanoes? Or just a happenstance of composition? The Moon is a concrete anchor for imagining exosolar worlds.
- troels 16y agoI talk out of my ass, by if I recall the numerous pseudo-scientific tv-show I've seen correct, the moon is pretty much similar to the Earth, but due to its smaller size, it has cooled down much faster. Additionally, it's not heavy enough to sustain an atmosphere, which can bind water to the planet.
- scotty79 16y agoLet's suppose there is a lot of water. Can you imagine weather at terminator with incredible winds blowing from hot side to cold side and back closer to surface and evaporating oceans on hot side that constantly rain down on the cold side of the planet? First order of business for any life that might arise there is to NOT catch the wind and NOT get in the flow.
- Tamerlin 16y agoI suspect that you're right about the weather, this would probably be a be a place with a lot of storms. On the other hand, if there's both sufficient water AND enough air for life as we know it on our planet's surface (excluding the extremeophiles like the flora living in Grand Prismatic Spring for the moment), the terminator wouldn't be nearly as clear as it is on Mercury, which has no atmosphere. Oceans of air and water would help to distribute heat throughout the world, much like they do here on Earth.
- hugh3 16y agoOn the upside, there's a tremendous amount of available energy for lifeforms to harvest. Here on Earth, life gets its energy from soaking up solar energy, or from eating things that have been soaking up solar energy, or from eating things which have eaten things which.... you get the idea. The sole exception is at deep-sea geothermal vents, where you can pick up energy from the thermal gradient. On Gliese 581g, there's huge amounts of energy to be picked up just from the constant flow of energy from hot side to cold side, so I'd expect lifeforms to somehow be tapping into that.
- scotty79 16y agoPiezoelectric tendrils gathering energy from ever flowing water. I like that.
- warfangle 16y agoAs was mentioned in another thread on another post on this topic: Given an earth-like atmosphere, the wind at the terminator would be a fairly constant 20mph from the sunward side to the shadowed side. Elsewhere, it would be slower. The upper atmosphere would circulate much faster than the rotational period of the planet, spreading the heat out pretty evenly over the planet. Given an earth atmosphere, and the same heat from the sun as the earth, it would be about 25F on the shadow side pole, and 135F on the light side pole. Of course, tectonics on a tidally locked planet are another thing, and if its surface has fused its atmosphere is probably chock full of H2SO4.