PASSING THROUGH: When a planet transits its star, passing in front of the star from an observer's vantage point, filtered starlight can carry spectral information about molecules in the planet's atmosphere. Here, Venus transits the sun.
Image: SDO/NASA
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The Best Science Writing Online 2012
Showcasing more than fifty of the most provocative, original, and significant online essays from 2011, The Best Science Writing Online 2012 will change the way...
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Even as astronomers work toward the hotly anticipated milestone discovery of an Earth-like twin orbiting another star, researchers are already asking what it will take to detect the existence of extraterrestrial life on such a planet.
First, the bad news: No telescope in existence seems to have the observing power to pick out the kinds of molecular signals that would indicate an exoplanet is habitable or even inhabited. On the bright side, observatories now being planned or already under construction could have a shot. But it’s hardly a lock.
The next generation of giant, ground-based telescopes, generically known as extremely large telescopes (ELTs), may be able to tease out biomarker signals from the starlight filtering through exoplanetary atmospheres, according to research recently published in The Astrophysical Journal and forthcoming in the journal Astronomy & Astrophysics. The two groups of scientists calculated what possible biomarkers might be detectable with the European Extremely Large Telescope (E-ELT), a planned observatory with a 39-meter primary mirror that would dwarf the 10-meter twin Keck telescopes now on the cutting edge of astronomy. (The Kecks can breathe easy for now: E-ELT will not come online until the 2020s at the earliest.) The results are cause for cautious optimism: assuming that Earth-like planets are relatively common, the E-ELT or a comparable observatory might be able to identify several molecules important to, or even indicative of, life.
On Earth living organisms leave numerous chemical imprints on the environment via, for instance, the production of oxygen by plants and bacteria, the release of methane during digestion, and the generation and consumption of carbon dioxide in the global carbon cycle. Measurements of those chemical species in an exoplanet’s atmosphere—particularly measurements that indicate a chemical cycle out of static equilibrium—could provide strong indications of the presence of life on that world. “By identifying certain molecules in the atmospheres of the planets, you can have some first proof that life is there,” says astronomer Ignas Snellen of Leiden University in the Netherlands.
Simply discovering extrasolar planets is difficult enough, however. Teasing out subtle chemical signals from the spectra of their atmospheres at such distances is a tremendous challenge. Nevertheless, astronomers using the world’s best telescopes have already identified specific atoms and molecules in the atmospheres of giant, highly irradiated exoplanets. To do the same for smaller planets in cooler orbits—objects from which photons are relatively scarce—will require much bigger telescopes and many years of observations.
With a high-resolution spectrograph to break down the collected light from an exoplanet into its component wavelengths, the E-ELT would in principle be able to spot oxygen gas in the atmosphere of a temperate, Earth-like exoplanet, according to the Astrophysical Journal study. On Earth oxygen predominantly originates from photosynthesis. “If there was no life, if there was no biological activity, this oxygen would not be there,” says Snellen, who led the study. Therefore, the presence of oxygen in an exoplanetary atmosphere would suggest a familiar process at work on a foreign world. “With the next type of telescope that will become available in the next decade, it will be very difficult,” he says. “It will be possible, but very difficult.”
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Add CommentBetter to build a giant rotating liquid metal telescope on the dark side of the moon. An excellent excuse to develop Moon industrial infrastructure. And create lots of jobs in a new non-destructive industry.
Reply | Report Abuse | Link to thisI'm with you there dwbd. Barring the moon scope perhaps we could build even bigger earthbound telescopes such as the "Monstrously Gargantuan Telescope" (MGT) or the even more massive "Oh My God That Is So F*&#ing Colossal Telescope" or OMGTISFC for short.
Reply | Report Abuse | Link to thisAny Moon based scope would cost tens of billions in infrastructure. A hundred orbitting and earth based scopes could be maintained for the cost. Also, a non- terrestrtialk based telescope is better for visible resolution but not so much for chemical analysis.
Reply | Report Abuse | Link to thisShear genius, not? Everyday photos and videos of E.T. craft are in the news, admitted some real some fake.
Reply | Report Abuse | Link to thisEven over the White House they buzz freely.
Presidents, Astronauts, CIA directors, 2088 pilot conformations and yes NASA's own video from the space station as of 3/7/13 show alien craft upclose, very good image.
It seems E.T. is hiding in plan sight but NASA the Gov. completely ignore even physical evidence.
How about this for a clue if we are alone and where to look. Message from Outer space unclassified by NSA
10/21/2004 approved for release by NSA under FOIA, case number 41472 written and decoded by Dr. H. Champaigne NSA technical journal XIV, no.1, 11 pages decoded.
The message was sent in response to Satellite Voyager message. The message decoded in part says they are our closet intelligent neighbor just 10.5 light years from Earth. The people live on 3 planets around their Sun with a population of 21 billion. They are a silicon base life form. There is life nearly everywhere and and a warning that some are not so friendly. Part of the message was redacted, about 1/5 blaked out. Only guessing what they said, maybe something like this, send me a message back with what E.T.'s are already in your solar system, we know most of them???
In late 2012 the NSA blocked access to the document for general public viewing as a link to it was posted on Twitter.
Advanced Alien races don't travel in space, to dangerous and to far, takes for ever, they use wormholes to travel, using Sun's as Star Gates in and out of the Universe, instead traveling into Sun spots and out. Our own Sun has had many Earth size Crafts observed around it and caught by the Solar Dynamics Observatory. So previlent and visible NASA shut down image viewing many times for the public. Hundreds of articles and videos from NASA's own live feed are on the web. I do think it's great to have new Scope's looking for E.T. but what about checking out a few that may already be here?
How ridiculous, there are no alien ships that have visited us. Period. Conspiracy psycho's.
Reply | Report Abuse | Link to thisOf course E.T. is not visiting our solar system, you know everything. The NASA video from the space station this week is simply a 1/2 mile long iceberg that makes 90 degree turns and slows and speeds up under it's own power. You are also smarter than two Pervious CIA directors who say E.T. is visiting Earth. You also can debunk 166,000 photos and videos, nearly 800 from NASA. You are one smart guy, your so afraid to even look at the evidence your about to have a heart attack, thinking someone may look at the NASA Space Station from 3/7/13 makes you sick. You are what is known by Scientists as a "Low Information Individual" (LII), most scientists do not say openly that Aliens are visiting Earth but know something is a foot. You would have to be dumb, blind and stupid not to examine the evidence or just so afraid of what might be your heart flutters.
Reply | Report Abuse | Link to thisYou also wish that all cameras and videos be confiscated so no more images of UFO's could be taken by the Illiterate public who take an average of 152 a day around the world. You sir (little s) are just not willing to have a reasonable discussion about anything that might cause you so much fear you might faint.
"...Any Moon based scope would cost tens of billions..."
Reply | Report Abuse | Link to thisYep for each and every important application for lunar settlement someone claims the same. But none of these persons ever open their eyes and think - duh, what if we developed the lunar infrastructure as a foundation of a VAST OPPORTUNITY to do Moon based telescopes and a thousand other important objectives simultaneously. Telescopes would be very cheap to maintain, build and operate on the Moon. Setting up the proper lunar infrastructure to facilitate that and a thousand other tasks is the important step. The slight gravity well of the Moon vs the much larger one of the Earth means you can easily launch materials to the Earth, kinda like rolling a log down a hill.
A moon rail launch, tether or elevator are all quite cheap methods of launching large amounts of materials off of the moon. And ultimately any nation that controls the Moon will be in control over the Earth. There would be no defense for any nation on Earth against a developed Moon colony. So if we don't do it, China will likely takeover the moon and we will all have to learn Chinese, and worship our new leaders in Beijing.
As soon as the budget is balanced ...
Reply | Report Abuse | Link to thiswe should spend more money on cancer research.
Does anyone seriously think that Webb Space Telescope will launch with the economic mess we are in?
Post a link to any one piece of evidence you say exists. I have studied the idea of extraterritorial visiting us. Besides the logic of some of the most intelligent people on the planet stating a resounding "no", also there is not one example or evidence that holds up to scrutiny. Hey, I got fooled by some friends in grade school that took a picture of a pie pan.
Reply | Report Abuse | Link to thisIf you can enlighten me with proof, let me see it.
@Ronnie Please get
Reply | Report Abuse | Link to this(a) psychiatric help
(b) a dictionary
@Ronnie Where are you getting your "information" from? Please tell me the names of the "pervious" (sic) CIA directors who say "E.T" (sic) is visiting Earth, and show me where we can find these statements in the public record. Also, what video from the space station are you talking about - provide a link.
Reply | Report Abuse | Link to this"LII" is not a recognized scientific term meaning Low Information Individual. You are making up these terms or someone is fooling you.
Please, for everyone's sake (including your own) try to exercise some rational skepticism and think more critically about what you say and believe in.
There are more than 9,000 high level individuals from Governments around the world who say a cover up of E.T. is underway and they were part of it. Ret. NASA officials have confirmed it to be true.
Reply | Report Abuse | Link to thisThis is just a few of over 1,355,000 links to videos and articles. Google search these and then hit me back. I have saved the best one for your come back.
UFO sightings by NASA Astronauts
CIA regrets cover up of UFO's
Roswell UFO Was Not Of This Earth And There Were ET Cadavers ...
Credible UFO sighting by pilots and crew in new UK files
New York Times UFOs: Generals, Pilots and Government Officials Go On the Record
Confirmed by NASA – UFO Footage from ISS Real | Veterans Today
Here are links to Testimony from America's top military, NASA, CIA, Astonauts and more, just google the link. I have saved the best for your reply. Sorry if your a Low Information Individual but you will wake up soon?
Reply | Report Abuse | Link to thisUFO sightings by NASA Astronauts
CIA regrets cover up of UFO's
Roswell UFO Was Not Of This Earth And There Were ET Cadavers ...
Most credible evidence of UFO's collected by UK
Credible UFO sighting by pilots and crew in new UK files
New York Times Generals go on record that UFO's are visiting Earth
UFOs: Generals, Pilots and Government Officials Go On the Record
NASA Officials confirm UFO's real and provide film footage
Confirmed by NASA – UFO Footage from ISS Real | Veterans Today
That's just the reaction I expected from a Low Information Individual, you don't and won't think about E.T. unless you speak in terms of Light years away. Your attack dog mentality is just SOP, act like an adult and have a conversation of just shut up.
Reply | Report Abuse | Link to thisThink about it, why not look in our own backyard for E.T. it won't cost $ Trillions.
Reply | Report Abuse | Link to thisLink to article: Confirmed by NASA – UFO Footage from ISS Real » Philosophers ...
Editor of World News Tomorrow, sent me the following story. He got it from a high level source at NASA and called in a favor, having the material and story validated through high level intelligence and law enforcement channels, official channels.
During the investigation, records of thousands of abductions were discovered, records of verified alien abductions, none of which were debunked. Information on this will be included below.
A month ago, Veterans Today published a classified analysis, including full scientific data, of a UFO video from South Korea.
These are the highest classified documents to have ever been leaked to the public, so far beyond the Pentagon Papers or anything Wikileaks has seen as to make make their efforts a joke.
Ronnie, you are a Low Intelligence Individual. :)
Reply | Report Abuse | Link to this350 of America's Highest ranking Intelligence offficers, Military men and Government officials testifying to E.T. cover up.
Reply | Report Abuse | Link to thisLink to video: U.F.O. Disclosure Project Full Version on Vimeo
Fear surrounds you like a blanket, truth can not be found in any words you say. You are just what I thought would come out of the wood work, sorrowful that anyone who might offer a different take on events are called names by you. I see men like you as mouthpieces for the cover up, even feeling sorry for you and your kind. Never will man be free of people like you, history labels them back stabbers, liars and low life's. You should try not attacking people but that is not in your DNA.
Reply | Report Abuse | Link to this"Satellite" Voyager is all I need to say about your post. Neither 1 or 2 is a satellite of Sol, never mind Gaia.
Reply | Report Abuse | Link to this"tens of billions in infrastructure"? What a way to create high-tech jobs.
Reply | Report Abuse | Link to thisSo, given that "shear", as opposed to "sheer", is used as the first word in your post, you think you have any credibility. Ouch; I, even with a B.S. Physics from a major university (hint: its one of those that don't 'officially' give athletic scholarships), wouldn't then espouse "facts" about ETs. Any life=form capable of faster than light travel (a necessity for ETs around earth) would either wipe us out forthwith, observe without our being aware, colonize us, or lose all interest. Hence, for continued sightings of ET craft to be credible they cannot come from one ET civilization capable of faster than light travel. Wouldn't at least one of those initiated contact? You want conspiracy on the part of gvt? Think WMDs in IRAQ and the "Patriot Act".
Reply | Report Abuse | Link to thisThanks for letting me play with your mind, just a few words and you freaked, I predicted it before I made the post. Your just as predictable as a gravity, you will fall for anything.... Thanks for being a predictable lapdog who has spent his life hiding behind his mothers skirt.
Reply | Report Abuse | Link to this"Better to build a giant rotating liquid metal telescope on the dark side of the moon."
Reply | Report Abuse | Link to thisJust to be pedantic, there is no dark side of the moon, only a far side. The moon is tidally locked to the Earth with 1 revolution = 1 rotation. But the far side gets plenty of sunshine during each month.
Over 2 decades to dedicated instruments, 1 decade of observation for ambiguous tests? :-/
Reply | Report Abuse | Link to thisThe only mitigating factor here is that habitable terrestrials seems to be much more common around M stars, and much more common than earlier believed. That may save some detection time.
Reply | Report Abuse | Link to this@Ronnie: "Of course E.T. is not visiting our solar system, you know everything."
Reply | Report Abuse | Link to thisWell, we know _that_. You don't need to know everything to know something. No observations, a lot of known false claims (high error rate), and it is unlikely because of the poor economics in visiting other systems except for colonization.
Of course something is a foot. A foot is a foot. E.T. is obviously not A FOOT. And how can a self-professed expert on U.F.O's refer to extraterrestrials as the star of a film playing John Williams in the background? Next up, Chewbacca will be a foot and he'll be teleporting through stars. Get a dictionary. Sorry George Lucas.
Reply | Report Abuse | Link to thisAs I'm writing this, instead of responding to Ronnie, it says I'm responding to null. I think he changed his name or something, probably going around to cause mischief, scientific uproars, etc. Most likely.
in response #18:
Reply | Report Abuse | Link to this"I see men like you as mouthpieces for the cover up, even feeling sorry for you and your kind."
He's one of the "others!"
Get 'em! :)