Other earths, circling different suns

December 5, 2011 11:21 AM

The Habitable Exoplanets Catalog is a database of the planets outside our solar system which are considered the most suitable for life according to certain steps and metrics. So far 16 have been identified as possible candidates. This Guardian article is a good introduction. You can also just dive into the catalogue, which ranks planets on two main scales, similarity to Earth and surface habitability (note that all images are computer renderings). The catalog is a project of the Planetary Habitability Laboratory at University of Puerto Rico in Arecibo (home to the world's largest radiotelescope).
posted by Kattullus (42 comments total)

From today, possible "earth 2.0" discovered
posted by The Whelk at 11:30 AM on December 5, 2011

Man it's not even worth building on Barren planets until you research Genetic Mutations.
posted by theodolite at 11:33 AM on December 5, 2011 [5 favorites]

Kepler 22-b or bust!!!!
posted by AElfwine Evenstar at 11:34 AM on December 5, 2011

which ranks planets on two main scales, similarity to Earth and surface habitability.

Habitability is important and stuff, but I'd like to see the list broken down into rankings for crime rates, public transit, and best dining.
posted by -harlequin- at 11:37 AM on December 5, 2011 [4 favorites]

Silicoids have no such restrictions, but you don't benefit from terraforming research.
posted by k5.user at 11:38 AM on December 5, 2011

If I learned anything from Star Trek it is that there's a shit-ton of Class M planets out there. Wake me up when they figure out where Risa is.
posted by birdherder at 11:40 AM on December 5, 2011

the biggest hurdle is of course, mindworms.
posted by The Whelk at 11:41 AM on December 5, 2011

and in other news: Astronomers Find Biggest Black Holes Yet
posted by gwint at 11:41 AM on December 5, 2011

The telescope is sensitive enough to see when a planet passes in front of its host star, dimming the star's light by a minuscule amount.

This would only work on systems where the solar disk is incredibly precisely edge-on when viewed from earth. How do they know which stars are likely to meet that criteria? Or is there a strong tendency to be aligned along the galactic disk which means the odds are more weighted to success?
posted by -harlequin- at 11:42 AM on December 5, 2011

i for one hope they welcome their human overlords.
posted by fetamelter at 11:43 AM on December 5, 2011 [4 favorites]

harlequin, it's all random. The technique is expected to miss a lot of planets, but it just happens to be within our technical ability to implement.

There's no strong affinity for the plane of the ecliptic to hew to the galactic ecliptic, as you can easily tell by looking at the Milky Way. Sol's own ecliptic is almost at right angles to the galaxy's.
posted by localroger at 11:44 AM on December 5, 2011 [2 favorites]

The Arecibo telescope is the world's largest single dish radiotelescope. And it's big.

But, more generally, the VLA is currrently the world's largest radiotelescope and, shortly, will be surpassed by ALMA.
posted by Ivan Fyodorovich at 11:46 AM on December 5, 2011 [1 favorite]

sometimes you don't wanna be subtle (NSFW text)
posted by The Whelk at 11:53 AM on December 5, 2011 [4 favorites]

Let's go! Shotgun!
posted by Meatbomb at 11:54 AM on December 5, 2011 [1 favorite]

Guys we haven't even talked to the space dolphins on Europa. They're not going to be happy if we skip the from someone outside the system.
posted by shakespeherian at 12:05 PM on December 5, 2011 [1 favorite]

Which one is the Wild, Chunky, Spunky Planet Of Mary Lou Retten Clones?
posted by Brandon Blatcher at 12:06 PM on December 5, 2011 [1 favorite]

sometimes you don't wanna be subtle (NSFW text)

Check out the Mare Imbrium. I'd like to see an ejecta blanket all over that crater. Aww, yeah.
posted by Smedleyman at 12:12 PM on December 5, 2011 [1 favorite]

The only two planets in the top 16 that are remotely near to Earth are HD85512B (36 lightyears away) and Gliese 581 b (20 lightyears away). The former has a surface temperature warmer than the hottest ever recorded on Earth, and the latter has a temperature roughly equal to a normal day in Antarctica. They both have a Standard Primary Habitability of exactly 0.00.

Am I reading this wrong? I was shot down last time I expressed a belief that there will be few to none properly habitable planets near to Earth, but it seems like that's a reasonable position.
posted by Jehan at 12:14 PM on December 5, 2011

I don't care about "other habitable planets." I want to stay on this one.

The very fact that folks are excited about such things frightens me and makes me feel that this planet has already been given up on.

Which makes me all kinds of angry and depressed.
posted by kinnakeet at 12:18 PM on December 5, 2011 [3 favorites]

Psh. Choosing a habitable exoplanet from a catalog is so gauche. I spend all my off-Earth time on a habitable exoplanet that only rich people know about.
posted by The World Famous at 12:29 PM on December 5, 2011

So where's the order button? Or do you have to get the print version of the catalog for that? I want to snap up KOI 610.01 before anyone gets there...
posted by Soliloquy at 12:41 PM on December 5, 2011

The very fact that folks are excited about such things frightens me and makes me feel that this planet has already been given up on.

I think you're seeing people's excitement not being so much these new planets will be great to colonize once we fuck up earth, but more of a "hey, we're not alone!" type thing.

To visit these planets we need the technology to travel multiples of the speed of light like in the movies. Or our alien overlords will need to be the same or we'll never have contact. It may happen someday just like it took a long ass time for the Europeans to develop the technology to discover the Americas.
posted by birdherder at 12:44 PM on December 5, 2011 [3 favorites]

Shipping's a bitch, and it doesn't qualify for Amazon Prime :(
posted by kcds at 12:59 PM on December 5, 2011

Sol's own ecliptic is almost at right angles to the galaxy's


...and when I look in a mirror I see there are no alien conquerors scooping my brains out with their greasy quivering proboscii, so that Security Through Obscurity thing seems to be working out quite nicely for us so far....
posted by CynicalKnight at 1:00 PM on December 5, 2011 [2 favorites]

The very fact that folks are excited about such things frightens me and makes me feel that this planet has already been given up on.

I may be married to this planet, but I'm not dead.
posted by Celsius1414 at 1:00 PM on December 5, 2011 [4 favorites]

It may happen someday just like it took a long ass time for the Europeans to develop the technology to discover the Americas.

Wait. What?
posted by The World Famous at 1:01 PM on December 5, 2011

To visit these planets we need the technology to travel multiples of the speed of light like in the movies.

This is understating the problem.

To send a generation ship that would let my great-to-the-nth grandchildren visit these planets eventually, we need new technology. Very hard.

To add a suspended-animation cargo bay that would let us visit these planets ourselves eventually, we need new science first. So hard we can't even guess how hard it is.

To send a faster-than-light ship that would let us visit these planets ourselves quickly, we need to overturn existing science first. So hard we have good reason to think it's literally impossible.
posted by roystgnr at 1:02 PM on December 5, 2011 [1 favorite]

We should totally shoot out a panspermia probe out there. We'll never see it, but we can seed it.
posted by Renoroc at 1:03 PM on December 5, 2011

I think we can get there if we pray hard enough.
posted by Renoroc at 1:04 PM on December 5, 2011 [1 favorite]

Can I just say that I think the NASA-approved definition of 'habitability' is total bunk (being the result of analysis of a sample size of 1)?
posted by newdaddy at 1:07 PM on December 5, 2011 [2 favorites]

The former has a surface temperature warmer than the hottest ever recorded on Earth, and the latter has a temperature roughly equal to a normal day in Antarctica.

Planets don't have "a" surface temperature, they have a range of surface temperatures from the poles to the equator. And extrasolar planets don't even have a range of known surface temperatures. You can get a black-body-equilibrium temperature from knowing how intense the neighboring star is and how hot the planet is, but tidal heating, radiogenic heating, and reflection/absorption in the atmosphere can change that a lot. Earth would be much colder without our greenhouse atmosphere's help.

Saying that these planets are habitable is wishful thinking; saying they might have habitable areas is reasonable.

Personally, though, I doubt that any technology which lets us send a colony that far will be particularly interested in the largest gravity wells at the end of the trip. It's as if monkeys debated whether the forest on the horizon has climbable trees, not realizing that the very skills needed to travel from horizon to horizon make tree-climbing moot.
posted by roystgnr at 1:15 PM on December 5, 2011 [4 favorites]

It may happen someday just like it took a long ass time for the Europeans to develop the technology to discover the Americas.

What about the Vikings/Chinese/Polynesians?
posted by CosmicRayCharles at 1:32 PM on December 5, 2011

So hard we can't even guess how hard it is.

So, really, it could turn out to be incredibly easy. Maybe it's just a matter of getting down just the right combination of b-boy moves and **pow!** there we are.
posted by The World Famous at 2:07 PM on December 5, 2011

I don't care about "other habitable planets." I want to stay on this one.

Well, you--along with anyone who thinks they've given up on the Earth--will be staying right here.

Knowing about Earthlike planets should be able to give us a better understanding of the Earth itself. We may be able to observe planets that are like the Earth but have slightly different conditions, or planets that are like snapshots of the Earth at different points in its "life cycle". So this doesn't have much to do with giving up on the Earth.
posted by polecat at 2:48 PM on December 5, 2011

I'll trade you two Hot Jovians for a Warm Terran and an Aggie.

OK, knuckle down.
posted by not_on_display at 4:16 PM on December 5, 2011

I don't care about "other habitable planets." I want to stay on this one.

We all love mother earth, some of us just think she should be the headquarters of the Galactic Empire.
posted by sammyo at 4:45 PM on December 5, 2011 [6 favorites]

also note that Kepler 22b does not currently qualify as habitable, it's too big, and classified as 'warm Neptunian'. so your bags can stay unpacked at the moment.
posted by OHenryPacey at 4:47 PM on December 5, 2011

I don't care about "other habitable planets." I want to stay on this one.

"Sure, it's breathtaking to look out and see the Earth. And probably, if someboy'd said before the flight, Are you going to get carried away by the Earth? I'd have said, Nah...yet when I first looked back at the Earth, standing on the surface of the moon, I cried. And if everybody had ever told me I was going to do that, I'd have said, "No, you're out of your mind."...Whether it was relief, or whether it was the beauty of the Earth, the majesty of the moment-I don't know., just every-you know, I never would've said I was going to do that. But I did."
-Alan Shepard, Apollo 14, who's not so complimentary nickname was "The Ice Commander"

It may be cliched, but there's some true to the sentiment that you have to leave home in order to fully appreciate it.
posted by Brandon Blatcher at 6:33 PM on December 5, 2011 [2 favorites]

Shepard's quote is the reason I think every politician should be required to take a ride into space right before taking office.

Some of them can even come back!
posted by miyabo at 7:55 PM on December 5, 2011 [1 favorite]

Planets don't have "a" surface temperature, they have a range of surface temperatures from the poles to the equator. And extrasolar planets don't even have a range of known surface temperatures.

I understand that the surface temperatures are mean values, but they still stand at -50C and 65C compared to the Earth's 14C. Some parts of those planets might be habitable, but other parts are far more extreme. Yet even if we find a planet with some parts we can reasonably tolerate temperature–wise, what about other issues such as gravity or the composition of the atmosphere? Even Mars—which sits so near to the Habitable Zone and has some promising qualities—isn't exactly teeming with little Tuscanies ready for us to colonize.

Let me know when they discover a planet which we can roll up and live on with worry.
posted by Jehan at 12:42 AM on December 6, 2011

What Does “Habitable” Mean?
posted by homunculus at 3:05 PM on December 6, 2011

Exoplanet Travel Posters
posted by homunculus at 12:29 PM on December 15, 2011