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Planetary Habitability Lab / UPR
This "periodic table" of exoplanets, including confirmed planets as well as candidates from NASA's Kepler mission, places exoplanets into 18 categories based on mass and temperature. The numbers keep track of how many worlds are in which categories. Click on the image to see a larger, more readable version.
Researchers have set up an online "periodic table" for extrasolar planets ranging from Hot Mercurians to Cold Jovians, with Earthlike worlds right in the middle.
The Habitable Exoplanets Catalog, drawn up by the University of Puerto Rico's Planetary Habitability Laboratory, is aimed at pigeonholing the hundreds of worlds that are being identified by NASA's Kepler space telescope and other planet-hunting projects. Eventually, the tally of exoplanets is expected to mount into the thousands, and that's where researchers hope the proposed catalog will come in handy.
"One important outcome of these rankings is the ability to compare exoplanets from best to worst candidates for life," Abel Mendez, the laboratory's director and principal investigator for the project, said today in a news release.
Also today, Kepler's scientists said they've confirmed the existence of their first exoplanet solidly within the habitable zone of its solar system, where water could exist in liquid form at a pleasant 72 degrees Fahrenheit (22 degrees Celsius). That certainly sounds livable, but Mendez told me that the planet, known as Kepler-22b, doesn't quite fit into the sweet spot for habitability because it's closer in size to Neptune than to Earth.
"I confirmed its radius, and Kepler-22b is a low-end Warm Neptunian, very close to a Superterran," Mendez said in a Twitter back-and-forth from NASA's Ames Research Center in California, where he was presenting his research at the Kepler Science Conference.
Neptunians are likely to have a gaseous rather than a rocky composition, which might make it tough for life as we know it on Kepler-22b. However, the situation might be more hospitable on a moon orbiting the planet, just as it is in the movie "Avatar" for the inhabitants of Pandora, a fictional moon orbiting the gas giant Prometheus.
How the catalog was created
The Habitable Exoplanets Catalog sets up a matrix of 18 pigeonholes based on temperature and mass: Planets in the Hot Zone would be too close to their parent suns for water to exist in liquid form. Water would exist only as ice in the Cold Zone, but could take liquid form in the Warm Zone. The catalog sets up six categories of planetary mass: Mercurians (think Mercury), Subterrans (Mars-size), Terrans (Earth-size), Superterrans (up to 10 times as massive as Earth), Neptunians (Neptune-size) and Jovians (Jupiter-size).
To figure out which planets fit which categories, the catalog draws upon a variety of resources, including the Kepler database of candidates, the Extrasolar Planets Encyclopaedia, the Exoplanet Data Explorer, the Earth Similarity Index, the Habitable Zones Distance metric and the Global Primary Habitability index.
The initial classification of more than 1,600 confirmed planets and yet-to-be-confirmed candidates puts only 16 potential worlds in the habitable categories — that is, Warm Subterrans, Warm Terrans and Warm Superterrans. But that list will grow: The Kepler team announced today that its tally of candidates has risen to 2,326, based on the first 16 months of the space telescope's mission. Forty-eight of those candidates are said to lie in their stars' habitable zones.
"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," Natalie Batalha, Kepler's deputy science team lead at San Jose State University, said in a NASA news release. "The more data we collect, the keener our eye for finding the smallest planets out at longer orbital periods."
Mendez and his colleagues are working on software to keep the Habitable Exoplanets Catalog updated. "The computers are doing the job," he told me. "I am trying to automate everything, but it takes time."
Right now, the world in the database that's judged most similar to Earth is a candidate known as KOI 736.01, which is 1,750 light-years away and is estimated to have a surface temperature of 55 degrees F (286 Kelvin). But the top prospect for surface habitability is KOI 255.01, a Warm Superterran that's 1,169 light-years away with a surface temperature of 86 degrees F (303 K). Some researchers believe super-Earths can be even more conducive to life than Earth.
Gliese 581d, a world that orbits a red dwarf just 20 light-years from Earth, shows up among the Sweet 16 on both lists.
The search revs up
So what's next? "I hope this database will help increase interest in building a big space-based telescope to observe exoplanets directly and look for possible signatures of life," Jim Kasting, a planetary scientist from Penn State, said in the Planetary Habitability Laboratory's news release.
A habitability index could help scientists set the priorities for future observations, but they don't necessarily need to wait until a new super-space telescope is launched. During the Kepler conference, the California-based SETI Institute announced that it was once again searching planetary systems for radio signals that could serve as evidence of extraterrestrial intelligence. Some of Kepler's planetary candidates are among its first targets.
"For the first time, we can point our telescopes at stars and know that those stars actually host planetary systems — including at least one that begins to approximate an Earth analog in the habitable zone around its host star," Jill Tarter, director of the institute's Center for SETI Research, said in a news release. "That's the type of world that might be home to a civilization capable of building radio transmitters."
Tarter and her colleagues makes use of the Allen Telescope Array, a network of radio antennas in northern California that had to be put into hibernation due to money troubles. The SETI Institute was able to restart work at the array thanks to contributions made by the public through the SETIStars.org website, as well as funding from the U.S. Air Force to assess the array's utility for space situational awareness (that is, monitoring the skies for hazardous asteroids and space debris).
Tarter said the highest priority would be given to Kepler planets that are located within their stars' habitable zones. But the search for extraterrestrial intelligence won't stop there.
"In SETI, as with all research, preconceived notions such as habitable zones could be barriers to discovery," she said. "So, with sufficient future funding from our donores, it's our intention to examile all of the planetary systems found by Kepler."
More about the planet quest:
- Which alien worlds are most livable?
- City lights could point to E.T.'s home
- Super-Earth on the 'edge of habitability'
- Interactive: How scientists search for planets
- Astronomers find 18 alien planets, and they're huge
Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.
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i find this so cool.
me too
Agreed, probably the most exciting astronomy going on today in my opinion is the search for Earth-like planets.
The only drawback to Kepler, which uses the transit method to detect planets, is that it is only going to detect planets that pass directly between the parent star and our perspective from Earth. Also, it is only working on a specific area equivalent to 1/400th of our night sky.
I'd like to see the circumstances of a particular star system itself drive the technology for a big space based (interferometry?) mission, so that we can determine whether there are Earth-like planets right in our cosmic back yard, orbiting specific stars like Alpha Centauri A and B, Tau Ceti, Epsilon Eridani, Barnard's Star, etc... all of which are roughly 5 to 10 light-years from Earth.
Then we could start thinking in realistic terms about interstellar probes within the 50 years or so that follow.
Personally, I'd like to see the development of new propulsion technology to go hand in hand with the ideas about interstellar probes. I think we should be working on the Alpha Centauri missions right now. It's good to come up with missions when you think it's impossible to accomplish a goal because (most of) the challenges are so glaringly obvious. We can actually use that fact to our advantage and come up with game changing concepts to account for the difficulties associated with such a challenging task.
Gentlemen (my apologies if one of you is a lady), I am afraid we are a long ways away from any interstellar probe that could return data to earth in a reasonable amount of time (say the lifetime of a human). I am very much in favor of developing better propulsion systems, but my expectations are more modest. I would just like to be able to navigate around the solar system more quickly. The recently launched Mars probe is going to take approximatelty 9 months to get to Mars. That's too long. Let's see if we can make interplanetary travel (manned?) more efficent before we start talking about sending probes to nearby star systems
With the current research being done in quantum entanglement that kind of communication may not be that far off.
I would tend to agree with you Mob, but I don't think it will occur until there is a very compelling reason to develop the probe itself... The discovery of a potentially habitable Earth-like planet within 10 light years from home would be pretty compelling. That's just based on known political and economic realities.
The studies have been done (Projects Orion, Daedalus, Longshot, Icarus, etc.) and concept proven (nuclear pulse propulsion). Most of the remaining R&D probably isn't likely to occur until the process of building a full scale spacecraft begins.
We're talking about a single mission that would cost well into the Trillions. No Earth part II, no interstellar probe... at least for the foreseeable future.
Now if we could only zero-point gravity-connect to their locations for instant access ... oh well, it's sure nice to dream!
.
Neat, I am gonna walk around all day wondering what kinda life might exist on a 72 degree water and land planet the size of neptune. Great. There are a lot of variables to speculate on. It would be helpful if we had found life elsewere at least we would have A data point to differentiate from our own to proffer up a clue. I can only guess that photoreceptors would be similar since the star is similar to ours, sound receptors seem take different forms here for several reasons, I can only guess what a denser atmosphere would evolve, me thinks of rhinos and elephants that pick up sound vibrations with their feet...and vegatation, I already know that gravity plays a big role coupled with indole3acetic acid....wonder how many ways the same effect is possible with different compounds....this is gonna go on for a while...I bet there are a lot of cool ideas out there in the realm of speculation....
there seems to be no key
what do the numbers indicate ?
this isn't helping understand anything
Well, the large numbers are obviously the number of planets in that category. If you click on the link Habitable Exoplanets Catalog you will find that M and R refer to mass and radius. Amazing what you can find in two seconds of searching for an answer, isn't it? :-)
You figured it out, Brokinarrow, thanks. The big numbers for all those categories will rise as more worlds are found. A lot of the smaller categories are grayed out because they haven't found planets or candidates for those categories (for example, Warm Mercurians). But that's just because the sensitivity of the search technique hasn't reached down to those sizes and distances yet. It's easier to find planets when they're bigger or closer in because they have more of a gravitational effect on their parent stars (or they look bigger when they transit their parent stars).
Are the mass and radius figures lower, upper, median values or something else?
?
Awesome find Alan, thanks for writing up an article on this! I've added their website to my favorites, will definitely keep my eye on them for future developments! Noticed that they are keeping track of potentially habitable moons as well, very cool.
thanks brokinarrow but a good article would not make me search for an answer ( was my point )
looks like you need a new sarcasom detector
I suppose I'm just tired of poorly done articles
Sorry that I did not notice your sarcastic letters there wade >.> /sarcasm.
Now you're making me feel bad, Wade-3708300!
Alan I assume you are the auther
please stop the fluff parts and get to the meat of the science , we the readers would not be reading this stuff if we didn't have some back ground on the subject
for those who don't have any back ground get soom ( book learnin )
I have a notoriously bad (non existent) sarcasm detector, but even I can tell that there is ZERO sarcasm in your original comment, wade.
As for your assertion that a "good article would not make me search for an answer", I have to disagree with that statement. A good article will cover a given topic to the desired level of thoroughness. Either the author or the person or company the author works for will set this "desired level of thoroughness". Frankly, Alan ran down all the information necessary dealing with this "periodic table". He brought your attention to it, describes what he feels important about it, and provides a link to the direct source. In my opinion that is all that is needed for a thorough article on the subject. Why would you want him to duplicate the work that has already been done on the page he links too? That is not very efficient now is it?
As Brokinarrow points out, there is a certain amount of info in the "periodic table" that would seem obvious to some people, but clearly not all people find it obvious. I guess it all depends at what level your understanding is, and in that case it is still best to simply link to the direct info so there is no chance that any info is lost in translation.
Fact of the matter is, if you want to really understand any subject in detail you will inevitably need to do some of your own footwork. In my opinion, you shouldn't rely on anyone else to spoon feed you your information.
Wade - Alan writes some of the most cohesive, coherent, and concise science articles you'll find. He is writing to broad audience, as he should on a main stream news site such as msnbc.
For "soom" one with such vast "book learnin" such as yourself, there are any number of "authers" and science publications that will give you all of the "science meat" you can chew (probably moreso ;)
One more strong argument that we need to get back into serious space exploration sooner than later.
What's the most gravity that a human would be able to stand on a foreign planet? 2-3G?
Depends on the human. Probably around 2g. We would adapt, the way we adapt to weight training... stronger muscles, connective tissue, and increased bone density.
But, how much would that suck at first... Here you are at say 150 pounds, then you suddenly find yourself on a 2G planet. You struggle to stand up because it feels like you've doubled your weight. I would guess that during the period of adaptation you'd really feel very sore quite a bit of the time.
If you're using acceleration as a means of artificial gravity, you could gradually up the acceleration en route, by the time you or your descendants get there, they will be able to walk the surface no problem.
You'd probably have to increase the air pressure too.
An excellent question. Most articles I can find are only related to g-force testing for pilots, which involves short term exposure to higher rates of g-forces. Not sure if there have been any studies done yet to test how longer-term exposure to moderate Gs would effect us. I think with a bit of training before hand 2 Gs would definitely be doable and maybe 3 Gs. We could also ship exoskeleton suits to aid workers that need to lift somewhat heavy loads on the planet, this is what we have NOW: http://www.youtube.com/watch?v=mO0xNI3xpmE So a full on Master Chief style suit isn't all that far-fetched once we are able to get to that new planet.
Again, you're on the right track. In comments to the the story cited below, I mention that other researchers have assumed that planetary gravity of 2.5 G's would not significantly affect the assessment of habitability (this research relates to a different planet known as HD 58812b). It would be pretty unbearable for a human who hasn't been accustomed to carrying around that much weight (e.g., 500 pounds rather than 200 pounds). But 500-pound humans do exist on Earth, so I think colonists could conceivably get used to it if they were conditioned for that G load. Also remember, G load does not scale directly with mass, because volume/radius have to be factored in as well.
http://cosmiclog.msnbc.msn.com/_news/2011/08/31/7546477-super-earth-on-edge-of-habitability
Excellent discussion. What about swimming. I imagine that if you were a 200 pound guy on Earth and find yourself under 2G circumstances you'd probably want to stay off your feet just like many of the 400 pound people you see wandering around walmart in the electric carts... But if you were swimming would the weight of the water pressing against your body feel doubled as well?
frank keep in mind if you dubble the planet size you don't dubble the gravity
Right, it's all about the density of the mass. But scientists have been doing calculations on these planets and should be able to tell how much mass and gravity would generated other than just it's X times bigger than the earth based on the shadow on the star. Just something else to think about regarding the new planets discovered and if human life could be supported. Granted life could live in all kinds of heavy gravity in smaller forms.
I'm not so sure that gravity would restrict the size of an organism. They would have evolved with the stronger gravity... we had very large beasties roaming the Earth at one point, and their demise had more to do with a lack of the resources they depended on for so long.
It's not hard to imagine that any creatures that evolve on these other habitable planets would be perfectly suited to handle that planet's environment. For example, the moon Titan (around Saturn) has liquid on the surface. It's perfectly logical for me to imagine something swimming around in that liquid. But that kid of organism would be vastly different to creatures we find on Earth because of the obvious differences between our places of origin.
In space, no one can hear you scream heh heh
But on the serious side, maybe it's time for us to build a ship to leave this sorry world. Let the Muslims and Christians have Earth as it seems they'll be killing each other forever taking as many of the atheist and innocents they can with them. That and in space, there is no east and west therefore it would be to much of a hassle to draw lines through the galaxy to designate an east for the Muslims so they can do their mesas everyday lol. Once many of us are gone, then they can kill each other to their hearts content.
How come people who hate religion have to make every article about religion, on matter what the subject of the article is?
well southerrebel I think its that we are still mad about the dark ages... yes 500 years of no science what a wast.
if man kind fails you can blame it on thouse 500 years just think of it this way ,we mite have solved the energy problem before we became overcrowded .
I find it interesting that you (canoworms) associate being innocent with atheism. Even if you don't think they are the same thing you still list them together as if atheists have not contributed to the world's ills. Frankly there are innocents on all sides, regardless of religion, and there are ...perpetrators on all sides, regardless of religion.
You can't just run away from conflict. That solves nothing. We as humans need to learn from our mistakes and move forward in a positive manner, otherwise all these things will follow in our journey to the stars.
well said Canoworms ....no war's where ever started by an atheist
Thank my nonexistent supreme being
There were plenty of wars started by pagans and such. Atheists are still human and just as capable of committing the evils a "true believer" would.
pagan dose not an atheist make.
pagan is an all encompassing term for religions out side the norm
an atheist is no religion therefor can't be included....so I stand by my statement.
You see, that one has sarcasm in it.
well mob_barley it is a statment of fact not sarcasm .no leader of any group anywere has profest aththeism and then started a war
I'm thinking the history chanel will help you
Lol, okay, but you can't sit there and tell me that no atheist has ever gone to war.
mob_barley why do you change the wording , I said start a war not gone to war its no wounder you don't seam to understand
it is most certain an atheist has gone to war ,forced to by some religious fanatice but not start a war
if you think I,m wrong name the leader, I,ll be waiting for this one
Good grief, Wade, are you serious? I'll just start with the obvious. Communist Russia and communist China are atheist by design. They have started a good deal of warring mischief on this planet.
no czeke thay are pagans occultist,buddhist,witches to name a few how ever none are atheist
Perhaps, Wade, you should have paid closer attention to the History Channel, as you recommended to someone earlier. Your inclusion of Buddhists with pagans, occultists and witches reveals your poor grasp of the subject. Virtually all of the communist nations were/are anti religious in all its forms. All that being said, I sense I am wasting my breath. I suspect you will simply accuse anyone of belonging to a cult of some sort when presented with evidence.
nice post. it is an interesting development and reserach attempt worth checking for updates.
could there be some order around planets, life genetics and periodic elements? see related discussion here: ellanti.wordpress.com
I am a habitable planet.
Maybe, but do tapeworms and hair lice really mean your habitable ?
Now, now, be nice... We are all walking petri dishes.
Never said I hated religion heh heh. Just commenting, being realistic and matter of fact. You're to sensitive.
No, you didn't say those words, per se, but you did make the point that you'd be just fine with leaving a good deal of them to kill each other.
My point is that this article has absolutely nothing to do with religion. Why not stick to the subject at hand?
Interesting article. The SETI folks continue to annoy me a bit... how can it be so hard to see that the window between when a civilization has built giant radio transmitters, and when it has colonized most of the galaxy, must be tiny on a geological timescale? And exactly how many decades of null results are required before we accept that either they're not out there, or they're hiding? I think the difficulty comes from watching too much Star Trek, and not appreciating that our current level is just one brief point on a much larger exponential curve.
However, there certainly are a lot of planets out there, and some of them may have primitive forms of life, which is exciting scientifically. So, hats off to the astronomers doing real science!
Mr. Boyle, my apology for disrupting your comment section.
Mr. Boyle, my apology for disrupting your comment section. However, I would like to comment on the article if I may. I've always enjoyed science and it's a shame all this is coming about towards the end of my life time as with many other discoveries. The changes I've seen over the years really astound me and that is a good article. It is good that they should catalog the planets as they go along as I'm sure there will be many more to be discovered. I've read many of your articles and hope you keep writing them. Just so I do not appear ignorant, I'm a Carl Sagan, Stephen Hawkins and Joseph Campbell reader/follower to name a few. Thank you
Other life form or not, just finding another planet to live on or that would be habitable for us humans would be awesome.
math proof of god( really short version-1 page- to get you interested)
onision.net/index.php?/topic/41844-math-proof-of-god-really-really-short-version/page__fromsearch__1
math proof of god (short version)
onision.net/index.php?/topic/41841-math-proof-of-god-short-version-update-all-youtube-videos-now-from-regular-site/page__fromsearch__1
math proof of god (normal version)
www.godlikeproductions.com/forum1/message1616159/pg1
a response to a set of objections
onision.net/index.php?/topic/42010-math-proof-for-cleb-answered-your-new-questions/page__fromsearch__1
A lot of evidence is provided in these documents--the second link, that shows how science is agreeing with these assessments.
Many respectable scientists and mathematicians, such as stephen wolfram, have also suggested this.
Many others object to the idea of a computation based universe due to
quantum computers, postulating that if a universe can allow for such a
computer, the universe would need to allow the computer to have a whole
other universe just to exist---I think this is wrong because even though
the quantum computer can simulate more information than all the
particles in the universe, as a higher level of complexity, it cannot
simulate anything higher, which the universe does. However, if this
trajectory of complexity were continued, such as the omega point
concept, you would get to a point of infinite complexity where the
universe and computer would both merge, being able to simulate the same
thing as it is simulating on the very wave function of the universe
itself.
If this indeed pans out, we may be able to tap into reality with our
mind and control it---I pose a simple thought experiment for this: in
any game ,if you know the optimum strategy it becomes meaningless to
play--like tic tac toe...perhaps this seperation we have of 'outside'
and 'inside' is what is causing our problems in physics...by behaving
and realizing the source code in the same way that 'reality ' does, we
then are functionally and on an information level, the same thing. Think
of 'Robert Heinlein's' 'groking...
with enough thought sharing between two people, if such were possible,
they would evcentually become one mind. Similarly, it is not irational
to assume that the more knowledge we attain of the universe the more we
will be able to manipulate it to such an extent that we merge with
it...like a computer program.
every trime we know more about biology or any other discipline, our
ability to control our environment increases. It makes sense that
eventually we will be able to control reality itself--the energy
requirement to do so decreases when you realize that intelligence is
just an energy efficiency function---the more intelligent we become as
we approach something like the singularity, the more of a 'cataylst; we
will be to any desired action with the level of energy required a
minimum, because the universe is essentially information.
The ultimate end then, will be our merging with it. That is the end
point of science ,as empiricism and tautological mathematical thought
merge.