French scientists reportable habitable planet orbiting another star
May 26, 2011 6:12 PM   Subscribe

French scientists have just published a paper entitled "Gliese 581d is the 1st discovered terrestrial-mass exoplanet in the habitable zone", claiming that their computer model suggests the exoplanet "will have a stable atmosphere and surface liquid water for a wide range of plausible cases." We've discovered a lot of exoplanets. And there are a lot of sites to help you keep track. Previously.
posted by Ipsifendus (47 comments total) 10 users marked this as a favorite
 
confirmed ... I do not think that word means what you think it means
posted by b1tr0t at 6:15 PM on May 26, 2011


Time for champagne!
posted by Blasdelb at 6:22 PM on May 26, 2011


there might be animals, specifically animals which have adapted to high gravity

As if 1 G is normal. Somewhere in the galaxy, an alien is looking at earth saying "there might be animals, specifically animals which have adapted to high gravity".
posted by stbalbach at 6:23 PM on May 26, 2011 [3 favorites]


Gliese 581d is the 1st discovered terrestrial-mass exoplanet in the habitable zone ... will have a stable atmosphere and surface liquid water for a wide range of plausible cases.

I totally read that to myself in a thick French accent.
posted by jabberjaw at 6:28 PM on May 26, 2011


Romanticize space.
posted by Mblue at 6:29 PM on May 26, 2011


"confirmed with a computer model"... perhaps I'll hold on to my skepticism a bit longer.
posted by underflow at 6:31 PM on May 26, 2011


If we send someone to check it out, we'll have our answer in only 600,000 years!
posted by briank at 6:35 PM on May 26, 2011


Excellent. Let's find some closer ones now.
posted by Meatbomb at 6:47 PM on May 26, 2011


20 light years away, in the scale of the observable universe, is virtually on top of us.
posted by Ipsifendus at 6:59 PM on May 26, 2011 [1 favorite]


Sadly, 20 light years away is still around or over 90% too far away. Probably good news for planet Gliese 581.
posted by uni verse at 7:02 PM on May 26, 2011 [5 favorites]


Do any of these planets have real names, names with more zip and panache than Star + Letter?
posted by jason's_planet at 7:07 PM on May 26, 2011


Then let's go! C'mon you bunch of apes, you want to live forever?
posted by wcfields at 7:09 PM on May 26, 2011 [3 favorites]


Dibs!
posted by Flunkie at 7:43 PM on May 26, 2011


It's sad - though perfectly understandable - that the first planet we've discovered to be anywhere close to Earth in its characteristics is still a comparative hellhole. What if most planets in the habitable zone are wrong in some way (too large a mass or tidally locked) to make them unEarthlike? Many star systems could have nothing close to Earth in planetary terms, and even those we do eventually discover may be so far away as might as to be unreachable in a realistic timeframe. If there's any lesson here, it's that Earth's not just rare, but pretty damn precious.

I look forward to the day when "another Earth" is actually found, but I don't know if it should be expected anytime soon.
posted by Jehan at 7:57 PM on May 26, 2011



I look forward to the day when "another Earth" is actually found, but I don't know if it should be expected anytime soon.


I'm fairly confident that within 5 years we'll know of so many ~1 earth mass planets in habitable zones around stars you'll have a hard time remembering them all (Kepler).

Within 10-15 years, we'll probably have spectra for them and know whether they have atmospheres affected by life processes (JWST, possibly certain land-based 'scopes like EELT).

Within 30 years, I'd say the odds are good that we'll have detailed enough pictures of some of them to see green continents and blue oceans (some future project).

I hope in my lifetime to know that there's life on hundreds of planets nearby.*

For galactic values of nearby.
posted by chimaera at 8:15 PM on May 26, 2011 [10 favorites]


I agree with chimaera. The whole progress of science has shown that the earth is not the centre of the universe or unique in any particular way but is actually a fairly unremarkable and common speck of dust in the infinite and there's no reason to think that the presence of life here is anything remarkable either. SETI has looked for intelligent life using radio technology but the failure to find it doesn't mean an amazing variety of life doesn't teem (relatively) nearby. We're at the cusp of a remarkable era and let's hope the inevitable discovery of nearby planets with liquid water and atmospheric oxygen (and therefore almost certainly life) sparks a renewed interest and investment in space exploration. Once we know there are planets with life out there there'll be a big push to launch bigger and better space based telescopes to image them and analyse their atmospheres and space exploration will once again have the purpose and excitement it's so obviously lacked since the moon landings.
posted by joannemullen at 8:27 PM on May 26, 2011 [3 favorites]


JWST

The mirrors for the JWST telescope are being developed by Axsys Technologies, based in Cullman, AL. Here's a video from Axsys showing how they just missed a tornado that destroyed downtown Cullman.
posted by stbalbach at 9:11 PM on May 26, 2011 [2 favorites]


Looks like there are around 117 stars within a 20 light year range. Gliese is just outside the scope of this map at 20.3 ly away. I wonder how many earth like planets there are within 20 ly?

On a side note I was pumped to discover that Wolf 359, as in the Battle of Wolf 359, is an actual star.
posted by AElfwine Evenstar at 9:17 PM on May 26, 2011


Do any of these planets have real names, names with more zip and panache than Star + Letter?

Eponysterical! Most probably they do, but it's a little hard to ask right now.

But actually, the IAU considers giving distinct names to exoplanets "impractical". A rebuttal of that consensus is here [pdf]. Some discovery teams may have unofficial names, though.
posted by dhartung at 9:26 PM on May 26, 2011


Within 30 years, I'd say the odds are good that we'll have detailed enough pictures of some of them to see green continents and blue oceans (some future project).

Do you have any reason to think this? My impression is that we're not even trying to look at planets (because it's a lost cause?) and are focusing on developing other methods of detection.

Supposing there is a way to identify a photon that came through the atmosphere of an exoplanet, how often would such photon arrive at a detector? Is building up spectra even feasible?

There is a retro-reflector on the moon. Shining a powerful laser back at yourself using the retro-reflector, my understanding is that you're lucky to get a few photons back, but since you are producing the photons with precise characteristics, you have a means to identify a photon as yours. I don't know how much of that attrition can be reduced by putting the detector out in space, but it feels to me like trying to directly view exoplanets might run up against limits of physics rather than technology.

Am I wrong? I'd like to be wrong.
posted by -harlequin- at 9:37 PM on May 26, 2011


a stable atmosphere and surface liquid water

and trees and piggies and...what's that, piggy? Well, I suppose it couldn't hurt to lie here for a momeohMYGODWHATAREYOUDOIgglgllrurgllee
posted by obiwanwasabi at 9:43 PM on May 26, 2011 [1 favorite]


My impression is that we're not even trying to look at planets (because it's a lost cause?) and are focusing on developing other methods of detection.

That last bit may be on the optimistic side, but I suspect that there may be a lot of momentum behind a projects like Terrestrial Planet Finder, Life Finder, and Planet Imager once we find planets with very strong indications of life:

The roadmap for planet detection goes (roughly) from Kepler, SIM (SIM-lite now), Terrestrial Planet Finder, Life Finder, and finally Planet Imager, which though not on any official budgeted roadmap any longer, is something scientists have been thinking about a fair bit. It would have the potential to get an image perhaps 25x25 pixels of an actual life-harboring exoplanet, which is just about enough resolution to make out continents and oceans.
posted by chimaera at 9:57 PM on May 26, 2011 [1 favorite]


TL;DR: Nulling Interferometry is a very young technology that is only going to become more precise and more powerful.
posted by chimaera at 10:00 PM on May 26, 2011


"Within 30 years, I'd say the odds are good that we'll have detailed enough pictures of some of them to see green continents and blue oceans (some future project)."

And how tantalizing would that be? Very tantalizing! Life just outside our reach... If we developed spacecraft just a little bit faster and tougher... That could be the spur that actually gets us to other stars, in person or robotically.

The coolest thing about this news is that it comes from a planet orbiting a red dwarf star. There's a crapton of red dwarfs out there, and they live forever compared to other stars. So if they can host dim, red-tinged biospheres, there might be a lot of earthlike planets to explore.
posted by Kevin Street at 10:01 PM on May 26, 2011


"The detection of biosignatures ... will probably have to await the launch of NASA's Terrestrial Planet Finder or ESA's Darwin mission. But if we are extremely lucky, ... current ground based telescopes are already up to the task provided many other "ifs" are satisfied. ... if the parent star is much smaller than the Sun ... harbors a Jupiter-like planet in a tight orbit ... [such that it totally eclipses the star and if it also has a]... second terrestrial planet, then its feeble reflected light might peek through during the total eclipse. ... "That would give us the chance to measure its colors in order to look for signatures of life. Said [Michael] Jura"

Quote from Strange new worlds: The search for Alien Planets by Ray Jayawardhana. Chapter 9, heading "Discovery Prospects. Page 223.
posted by ecco at 10:12 PM on May 26, 2011


There was a lecture about this recently on the "Big Ideas" podcast ( search for "Sara Seager on Exoplanets the Search for Habitable Worlds").

The methods we've used to detect exoplanets have, until now, only been able to detect very massive planets close to their star. Future projects will certainly be able to get a spectrum, which would allow us to determine if the atmosphere contains large amounts of water vapor or oxygen.

I also think we need to let go of the dream of visiting other stars within a human lifespan. Interstellar exploration, when it eventually happens, will be done by generational ships. The scales involved in space travel force us to think beyond our narrow, short lives.
posted by heathkit at 10:57 PM on May 26, 2011


In the car, driving my kids, the younger one (5) brings up how the sun is a star. I tell him yes, that's true, it is. The older (7) nods his head but I don't know if he really gets it I figure I'll give a little elaboration.

"So, at night, if you go out into the yard and look up at the stars, those are suns just like ours. Same thing."
I glance back at them in the mirror and I see he gets that. "And around those suns it makes pretty good sense to think there are planets and most likely, a few of them will even have, well, maybe people on them. So, while you're out in the yard, looking at some star wondering about who is one the planet that is revolving around it, maybe there's someone on that planet at that same moment looking up and seeing our sun and wondering about us."

I glanced back again, we were at a light, the older one's mouth was open, his eyes wide.
'Yes!' I think to myself, 'The future.'
posted by From Bklyn at 12:54 AM on May 27, 2011 [1 favorite]


I also think we need to let go of the dream of visiting other stars within a human lifespan. Interstellar exploration, when it eventually happens, will be done by generational ships. The scales involved in space travel force us to think beyond our narrow, short lives.

Sort of. Back in the 70's, some math was done (See Sagan's Cosmos), and while the engineering is currently well beyond us, it is theoretically possible to build a nuclear vessel that, over several years, accelerates to a tiny fraction of C, at which point relativistic time dilation brings the journey to easily within a human lifespan.

But not for any of us staying back on Earth (such as myself). As as we're concerned, we loaded a bunch of people on a ship, they left orbit, and were never heard from again. We'll never know if they made it, or if the thing sprang a leak and everyone died before they got a tenth of a way there.
posted by -harlequin- at 4:47 AM on May 27, 2011


around or over 90% too far away.

PERCENTS DON'T WORK THAT WAY
posted by DU at 5:45 AM on May 27, 2011


around or over 90% too far away.

PERCENTS DON'T WORK THAT WAY


Maybe they meant 90 parsecs, which would make sense, damn you George Lucas.
posted by jabberjaw at 7:09 AM on May 27, 2011


I'm fairly confident that within 5 years we'll know of so many ~1 earth mass planets in habitable zones around stars you'll have a hard time remembering them all (Kepler).

Within 10-15 years, we'll probably have spectra for them and know whether they have atmospheres affected by life processes (JWST, possibly certain land-based 'scopes like EELT).

Within 30 years, I'd say the odds are good that we'll have detailed enough pictures of some of them to see green continents and blue oceans (some future project).


That would be great, if true, and the science is in your favor. But for some reason I doubt it. Call me a pessimist - or just simply unimaginative - but I can't help but think that finding something close enough to Earth in its characteristics is going to be a one-off. When I think of all the frozen land and seas on Earth and the land to dry and hot to be habitable, it brings to mind all the small differences in climate that make our planet liveable. It's such a small gap to aim for.
posted by Jehan at 7:17 AM on May 27, 2011


Holy [Exopletive Deleted]!
posted by srboisvert at 8:04 AM on May 27, 2011


Within 30 years, I'd say the odds are good that we'll have detailed enough pictures of some of them to see green continents and blue oceans

You're confusing "Earth-like" with "exactly like Earth". The scientific definition of earthlike is a lot broader than what most people think of.

Consider Gliese 581d:

"It receives less than a third of the solar radiation Earth gets, and may be 'tidally locked', meaning that one side of it always faces the sun, which would give it permanent dayside and nightside...the denser CO2 atmosphere and thick clouds would keep the surface in a perpetual murky red twilight, and its large mass means that surface gravity would be around double that on Earth."

Potentially capable of supporting some sort of life -- yes. Exactly like the French Riviera -- no.
posted by CosmicRayCharles at 9:32 AM on May 27, 2011


Within 10-15 years, we'll probably have spectra for them and know whether they have atmospheres affected by life processes (JWST, possibly certain land-based 'scopes like EELT).

JWST is not really designed for that. Anyway, to really get accurate pictures and spectra on Earth-size planets orbiting other stars, you'd ideally need some sort of large-baseline interferometry. The best would be to have telescopes on Earth and on the Moon, giving the it effective size of the distance between the two.
posted by CosmicRayCharles at 9:40 AM on May 27, 2011


Couldn't you have satellite telescopes orbiting beyond the Moon, or do they have to be a fixed distance apart in relation to each other? In any case, yeah, there's no reason we couldn't build telescopes of various kinds capable of imaging exoplanets. That's only a short stretch from today's capabilities. We just need the will to do it.

In regard to traveling to planets like Gliese 581d, no doubt automated probes will make the trip first, just as they have in our Solar System. It would be quite a challenge to design a probe small and robust enough to travel at very high speeds, and a propulsion system that could take it there - but that's just the kind of challenge we need to grow as a civilization. Every generation or so we need to try for something that's currently beyond our reach. Right now it's fixing the environment, then hopefully space.
posted by Kevin Street at 10:38 AM on May 27, 2011


Potentially capable of supporting some sort of life -- yes. Exactly like the French Riviera -- no.

When there are tens, or hundreds, or thousands, the chances of finding something that has green continents (or blue-green, or red or any other photosynthetic color) and blue (for approximate values of blue as well) oceans gets better and better. Kepler is the mission that's going to give us a lot of statistics to give us confidence in the tens, hundreds, or thousands number -- and so far the indications are very positive with just the first 2 years of data.

JWST is not really designed for that.

True, but it's got MIRI (a mid-infrared spectrometer) so it can definitely find spectra for very good candidates (nearby, other favorable conditions), and EELT is definitely being designed for the type of spectrometry that we'd need for planets. If ESO had chosen to build OWL (a 100-meter telescope) it would have the angular resolution to find even more, and further away.
posted by chimaera at 10:52 AM on May 27, 2011


But not for any of us staying back on Earth (such as myself). As as we're concerned, we loaded a bunch of people on a ship, they left orbit, and were never heard from again.

Huh? Is this really true? At what point does "going really fast" become "completely invisible to viewers back on earth"? As long as they are going below light speed wouldn't they be able to continue to send messages back to earth and vice-versa, just with increasingly long delay times?
posted by Meatbomb at 11:00 AM on May 27, 2011


Yeah, they could send messages and telemetry back. Depending on how fast they accelerated, the messages would just get slower (providing a nice test of special relativity), then at the midpoint, presumably, they'd start to decelerate, and the messages would speed up again until they were once again transmitted at a normal rate.

And of course it would take longer for each message to arrive back at Earth. We'd wouldn't know for sure that they got to Gliese 581d until twenty years after the arrival.
posted by Kevin Street at 11:21 AM on May 27, 2011


Personally, I doubt that we'll find habitable worlds because humans benefit from three billion years of tightly entwined and mutualistic ecosystem development. But it should be interesting to say the least.
posted by KirkJobSluder at 11:35 AM on May 27, 2011


maybe there's someone on that planet at that same moment looking up and seeing our sun and wondering about us.

Can I buy some pot from you?
posted by banshee at 11:38 AM on May 27, 2011


it is theoretically possible to build a nuclear vessel that, over several years, accelerates to a tiny fraction of C, at which point relativistic time dilation brings the journey to easily within a human lifespan.

WHAT? What is that?

Personally, I doubt that we'll find habitable worlds because humans benefit from three billion years of tightly entwined and mutualistic ecosystem development.

Couldn't other planets have that too?
posted by Summer at 2:35 AM on May 28, 2011


Relativistic time dilation is a reference to the fact that time moves at different rates dependant upon whom you're measuring it against. For someone whizzing through space at a significant fraction of the speed of light, the outside universe appears to be in slow motion - but for the outside universe, it's the space traveler who's in slow mo. And they're both right.

So the space traveler can shorten his subjective journey by traveling faster and faster. For a trip to another star the outside universe sees him traveling slower than the speed of light (the ultimate speed limit), as his ship crawls between the stars for hundreds or thousands of years. But from his perspective inside the ship he's zooming through a crawling universe at tremendous subjective speed, and he can arrive at his destination in a mere handful of years.



As for the other point, KirkJobSluder is saying that humans evolved on Earth, so we may not be suited for any other environment. All the other planets out there, even ones that seem "earth-like," might be different from our home in one way or another, with various factors that make them unhealthy for us to live on long term. Different gravity, different magnetic field, different weather, just thousands of differences that could add up and interact in ways that would be impossible to adjust for.

I don't think that's necessarily true, but no one really knows. Until we get out there and try to live in non-Earth environments there just isn't enough information to say one way or another.
posted by Kevin Street at 3:12 AM on May 28, 2011


Couldn't other planets have that too?

I guess it means that it wouldn't be habitable by us... I don't know enough about exobiology, but I imagine there could be an ecosystem in which we'd find nothing edible and everything poisonous.
posted by Meatbomb at 3:26 AM on May 28, 2011


It's more of a biochemical compatibility issue. The biochemistry of animals on Earth was determined by the early dominance of cyanobacteria. Animals evolved to eat cyanobacteria and plants containing cyanobacteria at the base of the food chain, and compatible bacteria evolved to take advantage of the waste products of animal and plant metabolism.

But microbiology and organic chemistry offer other incompatible or toxic metabolic systems that serve equally well as the base of an ecosystem. For almost every complex organic molecule used by eukaryotic life on Earth, there's at least a half-dozen molecules with similar properties that can't be processed by our enzymes.

Just to start with, there's probably only a 50% chance that alien flora will have nucleic acids and amino acids with the same chirality. That's not getting into the dozens of micro-nutrients that vertebrates are critically dependent on other species to produce. There's no reason to assume that an alien ecosystem would have a source of compatible B-12 , offer an abundance of the essential amino acids, or that a planet's dominant autotrophs would create digestible complex carbohydrates.

And a part of my skepticism comes from the fact that the metabolic pathways we do have are buggy, often inefficient, and burn energy to get rid of toxic byproducts. So we can't say that any of them are chemically privileged. We inherited a metabolism that was arbitrary and just good enough to push the alternatives to the margins.
posted by KirkJobSluder at 5:56 PM on May 28, 2011 [2 favorites]


Actually, I think Frederick Pohl briefly explored the idea in one of the Heechee books of a failing human colony on a world that was almost perfect, except for the absence of a single vitamin that never evolved in the local flora.
posted by KirkJobSluder at 7:10 PM on May 28, 2011


If we did get to another star, it seems reasonable to assume that we'd bring our own ecosystem with us, in the form of plants and animals we could eat. Living on a toxic or otherwise incompatible world might require the sterilization of some isolated area like an island or upland, which could then be seeded with organisms more friendly to humans. But it would be frustrating to come so far and end up confined to a small space.
posted by Kevin Street at 8:21 PM on May 28, 2011


Can I buy some pot from you?
posted by banshee 2 days ago [+]


Dude! Totally not cool! How'd you get this number?
posted by From Bklyn at 12:46 AM on May 29, 2011 [1 favorite]


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