Kepler 22-b

[Menolly]

MOFFET FIELD, Calif. -- NASA's Kepler mission has confirmed its first planet in the "habitable zone," the region where liquid water could exist on a planet’s surface. Kepler also has discovered more than 1,000 new planet candidates, nearly doubling its previously known count. Ten of these candidates are near-Earth-size and orbit in the habitable zone of their host star. Candidates require follow-up observations to verify they are actual planets.

The newly confirmed planet, Kepler-22b, is the smallest yet found to orbit in the middle of the habitable zone of a star similar to our sun. The planet is about 2.4 times the radius of Earth. Scientists don't yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition, but its discovery is a step closer to finding Earth-like planets.

Previous research hinted at the existence of near-Earth-size planets in habitable zones, but clear confirmation proved elusive. Two other small planets orbiting stars smaller and cooler than our sun recently were confirmed on the very edges of the habitable zone, with orbits more closely resembling those of Venus and Mars.

"This is a major milestone on the road to finding Earth's twin," said Douglas Hudgins, Kepler program scientist at NASA Headquarters in Washington. "Kepler's results continue to demonstrate the importance of NASA's science missions, which aim to answer some of the biggest questions about our place in the universe."

Kepler discovers planets and planet candidates by measuring dips in the brightness of more than 150,000 stars to search for planets that cross in front, or "transit," the stars. Kepler requires at least three transits to verify a signal as a planet.

"Fortune smiled upon us with the detection of this planet," said William Borucki, Kepler principal investigator at NASA Ames Research Center at Moffett Field, Calif., who led the team that discovered Kepler-22b. "The first transit was captured just three days after we declared the spacecraft operationally ready. We witnessed the defining third transit over the 2010 holiday season."

The Kepler science team uses ground-based telescopes and the Spitzer Space Telescope to review observations on planet candidates the spacecraft finds. The star field that Kepler observes in the constellations Cygnus and Lyra can only be seen from ground-based observatories in spring through early fall. The data from these other observations help determine which candidates can be validated as planets.

Kepler-22b is located 600 light-years away. While the planet is larger than Earth, its orbit of 290 days around a sun-like star resembles that of our world. The planet's host star belongs to the same class as our sun, called G-type, although it is slightly smaller and cooler.

Of the 54 habitable zone planet candidates reported in February 2011, Kepler-22b is the first to be confirmed. This milestone will be published in The Astrophysical Journal.

The Kepler team is hosting its inaugural science conference at Ames Dec. 5-9, announcing 1,094 new planet candidate discoveries. Since the last catalog was released in February, the number of planet candidates identified by Kepler has increased by 89 percent and now totals 2,326. Of these, 207 are approximately Earth-size, 680 are super Earth-size, 1,181 are Neptune-size, 203 are Jupiter-size and 55 are larger than Jupiter.

The findings, based on observations conducted May 2009 to September 2010, show a dramatic increase in the numbers of smaller-size planet candidates.

Kepler observed many large planets in small orbits early in its mission, which were reflected in the February data release. Having had more time to observe three transits of planets with longer orbital periods, the new data suggest that planets one to four times the size of Earth may be abundant in the galaxy.

The number of Earth-size and super Earth-size candidates has increased by more than 200 and 140 percent since February, respectively.

There are 48 planet candidates in their star's habitable zone. While this is a decrease from the 54 reported in February, the Kepler team has applied a stricter definition of what constitutes a habitable zone in the new catalog, to account for the warming effect of atmospheres, which would move the zone away from the star, out to longer orbital periods.

"The tremendous growth in the number of Earth-size candidates tells us that we're honing in on the planets Kepler was designed to detect: those that are not only Earth-size, but also are potentially habitable," said Natalie Batalha, Kepler deputy science team lead at San Jose State University in California. "The more data we collect, the keener our eye for finding the smallest planets out at longer orbital periods."

For more information about the Kepler mission and to view the digital press kit, visit:

www.nasa.gov/kepler

[Vraith]

Only 600 light years away! practically next door, cosmically speaking.

[Avatar]

If there are 48 planet candidates in goldilocks zones, how come this is the first?

--A

[Savor Dam]

If there are 48 planet candidates in goldilocks zones, how come this is the first?

Maybe Bill Borucki is secretly a member of the Three Bears?

(FWIIW, Dam-sel and I used to work with Borucki 20 years ago at NASA Ames when she was secretary to Atmospheric Experiments Branch (his organization at the time) and I was managing desktop computer and networking support at that facility. Wow...long ago in a galaxy far far away!)

[Vraith]

More and more the odds tend to move towards my intuition that it's almost certain we'll find life somewhere else eventually...maybe all over the place.
Cuz I did some math. If we're in an average part of the universe, and there are two earth-like planets within 600 lightyears of each other, [both of which seem to be true so far] that means chances are there are AT LEAST:
4,000,000,000,000,000,000,000,000
earthlike planets in the observable universe.
and that's assuming life has to be in earthlike places, which I don't assume at all.

[I'm Murrin]

Average part of the universe would be empty space between galaxies, unfortunately.

[wayfriend]

If there are 48 planet candidates in goldilocks zones, how come this is the first?

It's the first candidate to be confirmed/validated. I guess they need to observe three transits to confirm.

[Vraith]

Average part of the universe would be empty space between galaxies, unfortunately.

Well, that's so, but I accounted for it. I could be off by a few zeroes either direction, cuz I pulled the numbers from memory...but what's a few orders of magnitude in numbers that size?

BTW everyone, if you have spare time, you can help try to find candidate from your own home. I think there are multiple places out there now, but I do this one from time to time:

www.planethunters.org/

[Did I first find that link on the watch somewhere? I might have...]

[Avatar]

If there are 48 planet candidates in goldilocks zones, how come this is the first?

It's the first candidate to be confirmed/validated. I guess they need to observe three transits to confirm.

Gotcha.

Anyway, largely agree with Vraith...not surprising...just a matter of time really.

--A

[Mr Hat]

Also interestingly it seems to have spurred the US military to chuck a load of cash at SETI to have a listen to it - www.theregister.co.uk/2011/12/06/seti_c ... xoplanets/

Although it's easy to jump on the conspiracy bandwagon with this, it's more to do with the fact that Allen Array that SETI uses is also very good at tracking stuff we've got orbiting around Earth.

[wayfriend]

As far as the odds of finding life go, my thinking is that it's not a matter of the odds of there being life, so much as it is the possibility of detecting it. The distances involed are freaking FAR. Technology and science can bring us new possibilities, but there's only so much radiation going from them to us, and if that radiation doesn't carry the information, it can't be found. (And even if it does, it would have to have been transmitted millions of years ago.) Short of a warp drive, the existence of ET life may be unprovable.

[Vraith]

As far as the odds of finding life go, my thinking is that it's not a matter of the odds of there being life, so much as it is the possibility of detecting it. The distances involed are freaking FAR. Technology and science can bring us new possibilities, but there's only so much radiation going from them to us, and if that radiation doesn't carry the information, it can't be found. (And even if it does, it would have to have been transmitted millions of years ago.) Short of a warp drive, the existence of ET life may be unprovable.

Yea, the detection is the problem...and time is too..even if we find the traces, it's possible they've gone extinct long ago, [or we have before anyone out there detects traces of us] and barring FTL, communication is problematic. [by which I mean almost impossible.]
The best way [expensive! never get the funding...and gov'ts seem paranoid about aliens so might not approve] broadcast everything we know in all directions on wavelengths that are fairly empty naturally at the highest power possible 24/7, and hope others are doing the same. Conversation wouldn't be possible...but think of the coolness of receiving a complete history of an alien civilization...arts, sciences, philosophies. boggles.

[I'm Murrin]

And imagine the turmoil if radio frequencies we make heavy use of were suddenly flooded with a constant stream of alien signals.

[Vraith]

And imagine the turmoil if radio frequencies we make heavy use of were suddenly flooded with a constant stream of alien signals.

Heh...a lot of the time I think that that is already the case.

Really though...that would be so cool! Certainly more interesting than political robo calls, butt dials, and drunken texting.

[Menolly]

I just think proof that life does or did exist elsewhere would be awesome enough. Doesn't matter to me at this time if there was anyway to learn much more than that...

[wayfriend]

Is it possible that extra-terrestrial life neither exists nor doesn't exist until we observe it?

[aliantha]

Is it possible that extra-terrestrial life neither exists nor doesn't exist until we observe it?

Dude. That cat's dead.

[Vraith]

Is it possible that extra-terrestrial life neither exists nor doesn't exist until we observe it?

Dude. That cat's dead.

Is not.

[Avatar]

...broadcast everything we know in all directions on wavelengths that are fairly empty naturally at the highest power possible 24/7, and hope others are doing the same. Conversation wouldn't be possible...but think of the coolness of receiving a complete history of an alien civilization...arts, sciences, philosophies. boggles.

Damn, that's just asking for trouble.

--A