December 5th, 2011
05:57 PM ET

Your thoughts: Search for life on other planets

Editor's note: This post is affiliated with the Overheard on series, a regular feature that examines interesting comments and thought-provoking conversations posted by the community.

Life, as we know it, needs certain conditions to exist. Readers yesterday had some strong opinions about searching for that life elsewhere, after NASA made an announcement about a new planet outside our solar system:

Edward: "The whole point of this is not whether we are going to get there. It is so people know that mathematically we are most likely not alone. So the more planets with possible water gets closer to proving that point."

nsr007: "You assume that other life forms need water to survive just because the ones on Earth do."

NASA scientists say the Kepler mission has uncovered its first confirmed planet in the "habitable zone" around a star, and are calling the discovery a "major milestone on the road to finding earth's twin." The Light Years post led to discussion about many meaty issues: spirituality, dealing with alien life-forms, space travel capabilities and the mind-bending size of our universe.

Planet confirmed that could have water

But a sizeable portion of the discussion was about what it really means for water to be on other planets.

dave: "Don't we know already know that there's water on Mars?"

Mike: "It's not known with certainty. That's a key part of Curiosity's mission. Also, although they failed to mention it, I think they are referring to planets in other solar systems."

The Professor: "Actually you are incorrect, there is and we do have proof of water on Mars, just in frozen form. There are signs of running water, but no actual firm proof of that. But there are changes that we have recorded through pictures taken using the MRO that show changes on the ground that could be attributed to running water. But the atmosphere of Mars is too thin to allow water to be in the liquid form for long, water tends to sublimate into water vapor quickly because of that."

T. D. Sharkey: "There is water all over the solar system in the form of ice; most water on Earth likely came from comets and other Kuiper type objects colliding with the Earth early in its history. Persistent liquid water is what they are looking for, and that is what defines a planet as being within the habitable zone."

Of course, the planet is 600 light years away, and readers debated the challenges involved in traveling such a distance:

minpin: "At 600 light years that would mean eight generations at average life expectance to reach it at the speed of light. Anyone want to volunteer?"

DT: "If you hit the speed of light, you will reach there in an instant. But, 600 years would have passed on Earth."

JeffinPDX: "If we invest in cryogenics, then yes, I would volunteer to be frozen and sent to explore an alien world."

What do you think about this discovery and the comments from readers? What thoughts and questions do you have? Share your comments below. Or, share your photos, videos and thoughts over at CNN iReport.

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Filed under: Kepler • News • Overheard on
soundoff (47 Responses)
  1. layla

    i was thinking, We all heard of "Aliens" being these green or grey creatures with super intelligence and highly advanced weapons but we've never thought that in another planet like this TWIN Earth planet there could be HUMANS. Exactly like us who just heard of a Twin planet of theres 600 light years away from them. If it were like the movies with these adavnced creatures, wouldnt they have should up here by now? I also agree with one of the comments above, we all assume that the aliens need water to live but what if they dont. THey could be creatures whho can stand extreme temperatures, hot or cold, desert like or plant like. FOr all we know the Aliens we are thinking of could just be living things like plants or animals. If we are meant to find these beings we will.

    March 25, 2012 at 5:14 pm |
  2. Jeff Malone

    Though we may look for life on other planets, the chance that we find life is greater in odds than scientist can estimate. An earth like planet has been discovered using telescopes, this is why AI (artificial intellegence) is important, A robot drone has a better life expectancy than a human being. A robot that can learn as the years go by collecting information and mapping ability for future exploration. Long distance such that of the earth like planet discovered is some 600 million light years away. This is my opinion, since the distance is years away we should concentrate our money for our solar system exploration and defense. A defensive system against asteroids, and meteors are far more important. If an intellegent life form finds us first, we should consider that a more defended earth is more impressive to any alien intellegences. The idea of self preservation should be the priority of the earth, duly with a structure that includes all nations of the earth. Our future should prioritize longevity before taking on long distant exploration projects.

    Jeff Malone Logan, Ohio

    January 2, 2012 at 3:30 pm |
  3. doug

    Hello puny humans i come in peace ( unless provoked ! )

    December 24, 2011 at 4:29 pm |
  4. sergio robles

    Every dimension has 1 degree off from the earths time. the real planet like awers is too the distant right of the moon and the north star Light years away but in my mind so close 2 know its there the mayan mentality still exist

    December 8, 2011 at 12:26 am |
  5. David

    This is all a waste of time and money. Vedic literature teaches us everything there is to know about this universe and our world in relationship to it. It discribes how there are millions of earths like ours with life on them. We are all being swindled out of our monies and resources so a few ego maniacs can indulge in some silly experiments, only to find out what real intelligent men already know. Hare Krishna

    December 7, 2011 at 7:56 pm |
  6. oneof7billion

    Every particle in my being tells me there is other life in the universe, however never in the history of this planet has there been a more dominate and destructive species that has changed this world on its own. Until new break throughs happen in science and a unity of all civilized nations it is just a matter of time when the planet can no longer sustain us. We are living longer and its just a runaway train. Other species are becomming extinct or on the brink. Question should be; Has the human race peaked in its development? Are we just another life cycle on this planet nearing its end? I hope not. nanu nanu

    December 7, 2011 at 5:37 pm |
  7. Madhup Rathi

    I do not understand why scientists are assuming that only water and only certain temperature is capable of harboring life. On another planet, another life-form may thrive on Methane & 500 degree temperature. DNA/RNAs are made from primary elements and some other primary elements other than carbon, nitrogeon can coalesce together to form DNA/RNA in some other planet. Heck, the building block is not necessary to be DNA/RNAs, it could be something else altogether!

    December 7, 2011 at 1:47 pm |
  8. Mark

    We now have observed enough planets to get numbers to plug into formulas to determine the likelihood of intelligent life. That number is 2 percent.We now know that on average 2 percent of known planets are in the habitable zone. If just 2 percent of those planets actually have life, then at least one of those planets in the habitable zone can be expected to have life. If just 2 percent of those planets have intelligent life, then we need to find about 2700 planets in the habitable zone before we find a planet with intelligent life. Given a galaxy of 100 billion stars, these numbers,if they hold true throughout the galaxy, mean 2 billion planets in the habitable zone, 40 million planets with some form of life, 800 thousand planets with some form of intelligent life, 16 thousant planets with some form of civilization, and perhaps 320 planets with advanced civilizations equalling or surpassing our own. It appears that Carl Sagan's theory that planet formation is an outgrowth of star formation and that life formation is a common outgrowth of planet formation may be proven true.

    December 7, 2011 at 4:16 am |
  9. Robert Kaiser

    Duh, If you know anything about math and space there is no way such a complex equation could only happen once.

    December 6, 2011 at 11:44 pm |
  10. Professor Trollworth

    Excellent! We have totally ruined this planet. Now we can move on to another one and ruin it too! Booya!

    Although we probably need to finish wiping out all the non-human species on this planet before we can really say "mission complete".

    December 6, 2011 at 11:39 pm |
  11. Tom Robson

    Super, another planet for us to ruin!

    December 6, 2011 at 11:23 pm |
    • RuinEarth

      Don't we evolve for the better according to "scientist"?

      December 7, 2011 at 2:42 am |
      • fimeilleur

        Evolution has nothing to do with better or worse, not in anyway that we can judge it. Since your post is an obvious dig on the scientific community, here's food for thought for you: The sooner mankind realizes that we did NOT inherit the earth, that we borrow it from our children and their children and all the other living beings on it; live in the present for the futur, and not live by the past for a supposed after life... the better.

        December 12, 2011 at 5:53 am |
  12. Dan

    People are missing the whole point of search for life on other planets. The Powers that run our world are hoping that if there is life, it won't be as advanced as our civilization. So they can TAKE over. CONTROL. Then the richest among us will go 1st to stake claim and govern, like it is here on earth. And the whole process will repeat itself, got it.

    December 6, 2011 at 11:16 pm |
    • Professor Trollworth

      I want to be governor. I would be a perfect choice for a candidate to run an alien world. Vote for me.

      December 6, 2011 at 11:40 pm |
  13. INOUT

    Why not look at this from the inside out ,maybe just maybe litfe on other planets dont live on the out side of the planets as we do on earth,Life is out there but nothing the way were thinking ,keep in mind all planets are living thinga even our EARTH ,water,air plants, the very core. We are just along for the ride .Think about!

    December 6, 2011 at 8:59 pm |
  14. Madeagle

    Riddle me this, riddle me that: Where has $1.3 Trillion disappeared to in multi-billion dollar increments? Every time there is a leak from the "three and four letter people" about something in space our deficit orgasms. Take a look at 1940, 1980, and now. The "War" don't cost that much. Anyways, our ozone and atmosphere is flat lining in some major areas. Polar ice caps are melting. There is freaking GRASS and TREES in Antarctica- Google it! Screw the 600 light year planet. What are our tax dollars working on now, in a time frame that "we" can reach or better yet afford; when this Planet craps itself tomorrow. Check out my website: If you purchase something or Christmas shop, maybe I could afford a seat on the "USS Brave New World Express."

    December 6, 2011 at 8:52 pm |
  15. dudley0415

    Fascinating observations. Trying to focus the beam for another, another, yet another, "Is there life out there?" debate is boring. Whatever is found in the future will be debated over and redefined unless they shoot at us. It's political, just like everything else. So, there's life out there – it changes my day-to-day life how, exactly?

    December 6, 2011 at 7:23 pm |
    • O.S. Bird

      Off the top of my head, current organized religions will self destruct, leading to new religions and new reasons to slaughter each other.

      December 6, 2011 at 9:25 pm |
  16. ken

    The headline should be "Life as we know it on other planets". Otherwise all probability calculations would be limited to our knowledge which may be only a fraction of Aliens' knowledge.

    December 6, 2011 at 6:30 pm |
  17. Thingsthatmakesyougohmmm

    Our government has already found something on Mars that they refuse to tell the world. Honestly, do you think with close to 40 missions to Mars they would come out and say, oh and by the way, we found these things? If our government could tell a lie about the wars they have created and spend trillions of dollars of your taxes and cover the truth up here on earth, what makes you think they would every tell the truth about something this significant. NASA has always been the puppet and the secret government the puppet master a we're here just enjoying the magic show. Even Clinton said there is a "secret government within the government" that didn't want even the president knowing what was going on.

    December 6, 2011 at 6:13 pm |
    • yeah-hmm

      Hopefully Wiki Leaks will let out some real data on aliens and classified technology, real soon. I'm tired of the stupid political crap they leak... time to leak something about aliens!

      December 7, 2011 at 2:58 am |
  18. Spock

    It's life, Jim, but not as we know it...

    December 6, 2011 at 6:00 pm |
  19. Judy75201

    Even if there is intelligent life on other planets, we will not ever come face-to-face with that life. If we were, it would have happened by now, and not in a field in the country where only toothless farmers live.

    December 6, 2011 at 5:57 pm |
    • yeah-hmm

      The evidence of life will open people up. Everyone seems incredibly up tight on this planet. We could use a good opening of the heart and mind.

      December 7, 2011 at 3:00 am |
  20. All for it. I'd even pay

    600 light years is a long way. I’d be more than happy to spend $100,000.00 to be frozen and to explore a new world. If space is ever privatized I’m sure some company will make the break through necessary to make prolonged life possible as well as deep space travel. These things don’t exist now because the masses (people in general) don’t want it to and won’t accept it. But once there is a choice I’m sure anything is possible. Look at where we were in the 10th century to where we are now in the 21st.

    December 6, 2011 at 4:56 pm |
  21. Mike

    I would loooove to see how the Church is going to explain extra terrestial life...

    December 6, 2011 at 3:27 pm |
    • Oldtimer

      Which church. I am Mormon and cannot speak for the Church of Jesus Christ of Latter-day Saints, but as for myself, I do not doubt there is life on other planets. I see no inconsistency between believing God created this world and sent His Son and our Savior, Jesus Christ, here and intelligent life be elsewhere as well.

      December 6, 2011 at 5:18 pm |
    • Kc

      Go back under your rock fool

      December 6, 2011 at 5:20 pm |
    • Mike

      Easy one... God created life on Earth and all over the multi-verse. To think that God only created life on Eath and then stopped is silly. Life is everywhere and God is God! Thats what I believe.

      December 20, 2011 at 2:50 pm |
  22. James Harrison - Saint Petersburg, FL

    If our planet has taught us anything it is that life can exist in even the most extreme environments which makes me believe that life in our universe is not just an exception to the rule, it is the rule. What would be the point of a universe as vast and beautiful as it is without many different observers from many different vantage points?

    December 6, 2011 at 12:17 pm |
    • framore

      Agreed 100%. Life just is.

      December 6, 2011 at 7:43 pm |
  23. Guest

    Im still working on discovering Intelligent life here

    December 6, 2011 at 12:03 pm |
    • Thingsthatmakesyougohmmm

      Lets start with you leaving and then we'll be just fine!

      December 6, 2011 at 5:46 pm |
  24. Robert

    I have a problem with how "habitable zone" is defined. To me, that is nothing more than injecting our own biases (based on life forms on earth) as to how all life forms survive. Surely, at other temperatures and pressures, different molecules can become biologically useful. Perhaps "life" may not even have to be carbon-based, or, there is a continuous spectrum of usefulness for particular compounds to be biologically useful with which different complexities of "life" (again, a spectrum) can be created. But at least, it seems mathematically improbable that Earth is the only place in the universe capable of supporting life.

    December 6, 2011 at 11:56 am |
    • will

      We use the "habitable zone" because we know matter-of-factly life can exist there. How do we know? Because of Earth. No one is saying life cannot exist outside those parameters, the habitable zone is just where other life forms similar to humans could survive. It's the best place to start looking. Stop whining about the "arrogance" of humans.

      December 6, 2011 at 12:17 pm |
    • Emma

      I always think about this! Who are we to define what life is? Why does it have to be carbon-based?

      December 6, 2011 at 3:39 pm |
      • shazam

        life is carbon based because carbon atoms are easiest atoms to build something, they have 4 valence electrons so they are able to share/take 4 more electrons.

        December 6, 2011 at 5:50 pm |
    • badidea

      I think the point of looking first in the habitable zone is that we know for a fact life can live where we can live. It's our only reference point right now. Once we meet life that isn't carbon based, needing water, etc. then we can expand our definitions and our search parameters.

      December 6, 2011 at 4:47 pm |
    • lost in space

      I agree, hope,dream that there is more out there, cause if what we have achieved is it. Its sad. Our ancientors built structers so Mich more solid than us. We still fathom why and how they accomplished such a feat, our today's technology and assembly has achieved nothing as far as carrying our name. As a forigener what would you believe as "commitment" a pyramid of 1 ton bricks or a skyscraper 120 stories highroad made of crap and glass. Not saying put engineering is bad. Bit ours WILL NOT stand the test of time. Lets not even begone on our record retention. I believe we have already been visisted, part of our Biblical stories are a reflection of a bigger story. And in the end, we are right where our ignorance allows is to be.. which is not a bad thing.

      December 7, 2011 at 10:08 pm |
    • PNNH

      The habitable zone is generally defined as the region that has liquid water.

      January 3, 2012 at 11:18 am |
  25. miguguel dones

    wuich of the AMERICAS. ?

    December 6, 2011 at 8:50 am |
  26. rebelcell

    Although the thought of reaching such a goal is without a doubt amazing.
    We will not achieve this through our society(global).Earth is doomed.

    December 6, 2011 at 8:11 am |


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