New Telescope Could Reveal a Milky Way Packed With Habitable Planets

By Eliza Strickland | February 26, 2009 5:13 pm

exoplanet earth-likeWhile astronomers have found more than 300 planets beyond our solar system in the last 15 years, none of those “exoplanets” has been a likely candidate for extraterrestrial life. The exoplanets discovered thus far are all either too close to the hot sun or too far away and therefore too frigid to host life as we know it. But Alan Boss says it’s just a matter of time before we find Earth-like planets in the “Goldilocks zone”: he calculates that 100 billion of them may exist within our own Milky Way galaxy. And NASA’s Kepler satellite, which is expected to launch on March 5, may be the key to finding them, he says.

Boss, an astrophysicist and author of the new book “The Crowded Universe: The Search for Living Planets,” says that if any of the billions of Earth-like worlds he believes exist in the Milky Way have liquid water, they are likely to be home to some type of life. “Now that’s not saying that they’re all going to be crawling with intelligent human beings or even dinosaurs,” he said. “But I would suspect that the great majority of them at least will have some sort of primitive life, like bacteria or some of the multicellular creatures that populated our Earth for the first 3 billion years of its existence” [CNN].

Europe’s CoRoT satellite has already discovered several fascinating exoplanets, including a rocky world that’s about twice the size of Earth but devilishly hot due to its tight orbit around its sun. Both CoRoT and the soon to be launched Kepler use the transit method to detect new planets, in which the subtle dimming of a star’s light reveals a planet passing in front of it. The Kepler telescope will gaze continuously at 100,000 stars in two constellations known as Cygnus and Lyra for more than three years. “Within three to four years from now, these telescopes will tell us just how frequently Earths occur. It’s an exciting time to be alive,” Boss said [The Guardian]. However, CoRoT and Kepler are unlikely to detect any signatures of actual life on exoplanets; that daunting challenge will be taken up by the next generation of space telescopes, Boss says.

Kepler’s sensitive telescope is expected to pick out rocky planets that are not only roughly the same size as Earth, but also orbit their star at a roughly equivalent distance. But that won’t happen right away, Boss explains. It takes at least three orbits for astronomers to confirm that the dimming of the star is really caused by a planet rather than, say, the brightness cycles of a variable star or a binary-star system. If the planet is extremely close to its star … that won’t take long. For example, the hot super-Earth identified by Corot completes an orbit in just 20 hours. Farther-out planets will require more time to orbit, and therefore more time to detect. “The earth, by definition, will take at least three years to get,” Boss said. “Roughly four years from now, we will be beginning to make our claims for Earthlike planets around solar-type stars” [MSNBC].

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DISCOVER: How Long Until We Find a Second Earth?

Image: NASA

  • Tom Tinney, Sr.

    Alphabetic History of Civilization:
    Ancient and Modern Genealogies
    . . .

    And were it possible that man could number the particles of the earth, yea,
    millions of earths like this, it would not be a beginning to the number of His
    creations; for His curtains are stretched out still; and yet He is there, and
    His bosom is there; and also He is just; He is merciful and kind forever;
    peace, justice, truth and mercy go before His face and have no end.

    The Family Genealogy & History Internet Education Directory:
    Scholarly mega site map of world wide Internet resources.

  • Dave

    Statistically there’s no way we’re alone — and demonstrating this will only reinforce that we humans are NOT special. We are distinct from the animal kingdom but we’re a part of it, and so too would alien (relative to our planet) life be a part of some fantastic tree of life.

    Life elsewhere makes Earth far less special (and certainly undermines the notion that “God” played out his theatrics on this planet).

    God, fundamentally, remains a manmade idea, projected upon the cosmos.

  • George

    * The Independent (16 February 2009)- There’s another Earth out there – and we’ll find it – Habitable planet could be located in the next four years, scientists say… The first Earth-like planet orbiting a distant star could be discovered within four years, astronomers believe:
    * JAPANESE SCIENTISTS EYE MYSTERIOUS “PLANET X”-The researchers at Kobe University in western Japan said calculations using computer simulations led them to conclude it was only a matter of time before the mysterious “Planet X” was found:

  • Tony Cisco

    Your hypothesis is dead on up until when you get to the part that says,”Life elsewhere makes Earth far less special”(“and certainly undermines the notion that “God” played out his theatrics on this planet”).

    Why would it undermine that belief?

    Even if science proves that there is intelligent life on other planets and they can sustain life in the same way it does on earth.(And I believe that there is more and less intelligent life elsewhere)..It does not mean that earth was not created for humans by “God” just because of proof of extraterrestrial life elsewhere!

    Hypothetically speaking; If you built a house according to a standard blueprint and you built others that did not necessarily depict your talent exactly ..You just kept building until one day you say.. I am going to build something extraordinary..Something that really depicts me as a who I am..Then you design and build a specific model of you…A house that when others look at it they say..Yeah that’s him alright! It has your specific signature on it because of the special way that it is built..

    You would not be discredited that your work is not special because you have built 100 trillion or so others.. Its just that particular model is you. And that my friend would be pretty special!

    As it has been written: “God created man in His own image, in the image of God He created him; male and female He created them.” According to your statement does that mean “God” did not create other intelligent life elsewhere also but just not in his own image.

    I believe that by “God” creating a carbon copy of himself or us in his image, the most powerful entity in the universe will remain pretty special to humankind no matter what they find out there.

    Faith isn’t something that can be reasoned away by science or anything man can conjure up.

    Nice try though. :)

  • averageiq

    Faith is something that can be reasoned away by science, agreed!

    However, science cannot be reasoned away by faith either.

    God gave us brains to use them. Thank God.

  • zachary

    Yeah, and which religion exactly holds that belief to be true? You are positing an ad-hoc supreme being simply because you like the notion of God. With no reason at all, and no religious foundation for the belief in a God that did trial and error “testing his skill.”

    Sadly you are right, faith, belief in something that cannot be proven, cannot be reasoned away. We will still try though, until people stop considering “faith” something to be proud of.

  • Derek Douglas

    As Dave said, its fundamentaly a man made idea, the arrogance of our species to think we are the representation of the creator of the universe, is beyond belief! If there is intelligent life out there, lets just hope they have reached a point where the need to hold on to the invisible man in the sky has been irradicated. People like Cisco dont look at ideas or try to find new ones they spend all there time trying to make sense of whats going on around them by changing fact or even what gods words are (in there opinion) to suit there beliefs. So many people believe in god not through choice but because there parents told them they had to, educate your children and give them options and a choice.

  • GH

    It’s hard not to conclude that all useful knowledge and science are an accumulation of an ever more accurate classification, of categorizing the location, behavior and relationship between things. Each succeeding computer advancement is ever more capable of storing more information. It should surprise no one that virtual reality comes ever closer to visually simulating the complete accurate replication of animate objects, of life itself. This unlimited exponential capability may some day reach under the quantum probability of what is with such command of subatomic behavior that no one will need to go anywhere without first knowing what the likey trip will be and what will be encountered there. At some point the machines created for the trip will merge with the planned excursion and there will be no difference in time, location or experience.

    Right now it may be impossible for anyone to envision their beginning or their end or an existence without end. We only know that, commpared to an earlier part of our life, each succeeding point in time is a smaller fraction of the whole. Each experience seems to pass more quickly. Then what is this? Are we a smaller fraction of something before. If we define our existence in time and place — accepting a point in infinity — then where do we exist at all? Likewise, no one can imagine a fixed beginning to the universe, an end to the universe or an existence without end. We are hardwired to a perception in between, a relative position. If we begin to accept that our universe is everything ever created we want to know what came before. Perhaps an existence as we know it began with our universe at the end of another. Perhaps the first life as we know it became the first enduring intelligence. Perhaps that first intelligence, 14 billion years ago, evolved and spread to all corners of its realm. Perhaps it created life as we have. Perhaps it observed evolution all around. Perhaps its knowledge and its limits expanded beyond the question of what begins and what never ends, and knows all, knows of us and everyone, and everthing that ever lived and ever will. Perhaps the greatest benefit of knowing is knowing relative to another view. Perhaps what we want and need is empathy for our view in our tiny part of the universe and reassurance that we are important, and not forgotten on our trip. Is that what God is and what we are? Or are we seeking the next best thing, someone like ourselves with whom to empathize on the way, whatever our fate, long or short?

    All the stars are but grains of sand, and thence from all the beaches of the world — thus is our universe. However, rarely does a grainy star share so much as a grain’s distance to another, and many are a sea apart.

    There can be no proof of life anywhere beyond ours. Nor can there be proof of other intelligence. This is a fact until proved otherwise. But not long from now the day will come when other life or other intelligence shall be the established truth, and one will ask the other about God.

  • Mike Donohoe

    I feel that life exists because that is a thrust of nature, rather than as once seemed to be fashionable that the emergence of life is a weird mathematical anomaly.

    I find it amusing that if this was the only planet with life, to some that means biology and by extension consciousness are purely random byproducts of nature, where if there is life elsewhere, that means that the existence of life is no big deal. The opposite could be said in either case, too. As far as I’m concerned, there is nothing in conflict with science in the idea that the cosmos is, itself, an immense organism.

  • phil spector

    Would it be possible to build a telescope or other device that could directly see or detect other planets?

  • Eliza Strickland

    @phil spector: Good question! It’s tricky, but astronomers have actually directly spotted a few exoplanets. This post from a couple of years ago describes how they caught sight of a planet named Fomalhaut b.

    — Eliza, DISCOVER online news editor

  • festival music

    Sometimes its better to just step back and realize that not everyone shares your beliefs


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