'Tatooine' gives first direct proof of 2-sun planet
This iconic "Star Wars" scene inspired the nickname "Tatooine" for a newly found 2-sun planet Kepler-16b.
September 15th, 2011
02:00 PM ET

'Tatooine' gives first direct proof of 2-sun planet

Luke Skywalker looks out over a desert dominated by two setting suns in an iconic scene from "Star Wars Episode IV: A New Hope." But this isn’t just the stuff of fiction. Now, astronomers have confirmed the first direct evidence that planets with two suns do exist.

Scientists at NASA and the Search for Extraterrestrial Intelligence Institute [SETI] are informally calling the newly discovered world Tatooine, as homage to Skywalker's planet imagined by George Lucas.

The so-called circumbinary planet has been dubbed with an official name that's much less interesting: Kepler-16b.

Unlike the tagline of the Star Wars saga, Tatooine is not located in a "galaxy far, far away," it's right in our own backyard - relatively - about 200 light years from Earth in the constellation Cygnus. Getting to Tatooine aboard a spacecraft traveling at light speed - 186,282 miles per second - would take about two centuries. (The closest star to earth outside our solar system is about 4 light years away.)

Using data from NASA's $600 million Kepler telescope now orbiting the sun, a team lead by SETI's Laurance Doyle detected the actual shadow of a planet as it crossed in front of its two suns - a scientific first. Before this discovery, astronomers could only infer that planets could circle two suns by looking at how the timing of the eclipses of those stars changed. 

If the eclipses had happened at different times than expected, that would indicate that the stars may have a planet. But many other factors besides planets can cause such behavior, "so we really needed to see" the planet's shadow crossing in front of the stars to identify it without a doubt as a circumbinary, Doyle said.

"When we first discovered it … I sent around a message, 'Hey, you know guys, we should ask George Lucas if we can nickname this guy Tatooine,'" said Doyle, a former protegé of famed astrophysicist Carl Sagan. "Suddenly and unexpectedly after years of looking for a circumbinary planet – we got a beauty."

The discovery opens up a whole new world of questions about the formation of planets, double-star systems and the way they work together.

A double sunset on the real Tatooine, Doyle said, would surpass even Lucas' imagination. For someone standing on the planet's surface, one of the suns would appear orange and the other red.

The suns also change positions and movement in relationship to each other. This means sunsets on Tatooine are like snowflakes: No two are ever the same. "Sometimes the red star would go down first, sometimes the orange star," said Doyle. "Sometimes they would be far apart, sometimes they would be eclipsed. So it's a really interesting sunset."

Inside the rooms of SETI and NASA, the word's been spreading fast. "Everybody's already referring to it in informal meetings," said Doyle. "'So, how's Tatooine going?' or referring to 'Tatooine's orbital period,' or whatever."

The idea that something that was science fiction in 1977 has been found in the real universe in 2011 could, Doyle hopes, inspire future scientists and astronauts.

But future space travelers may be disappointed to learn the real Tatooine probably isn't home to Skywalker or any other life form. Doyle is highly doubtful that the planet could support life as we know it due to its size and distance from its suns.

Here are a few other details about the planet nicknamed "Tatooine."

  • The planet could contain water in some form.
  • It's possible the planet could have one or more moons. Doyle continues to search.
  • Kepler-16b will be visible to amateur astronomers in June 2012.
  • Kepler-16b is the best-measured planet outside our solar system.
  • Its two suns go around each other every 41 days.
  • The planet has two eclipses each month.
  • Kepler-16b's "year" - the time it takes to go around its double suns - is 229 days.
  • It's believed that double-star systems outnumber single-star systems.
  • Doyle expects to find more circumbinary planets in the next month or two.

Kepler-16's mysteries began to reveal themselves in March of this year, when Doyle and SETI colleague Bob Slawson found the first clues while working at SETI facilities in Mountain View, California. Further investigation showed the system contained two small stars and later, a planet circling the stars. 

"It was really quite a team effort," said Doyle. "Dan Fabrycky, at University of California, Santa Cruz, did gravitational confirmation calculations.” I asked him, 'So, what did you get?' He said, '99.99%, it's a planet.'" Then after a few additional confirmations from other team members including Harvard-based Josh Carter, "we were like, that's it guys. We nailed it. That's the moment we nailed it."

The discovery reminds Doyle of the work he did with Sagan at NASA's Jet Propulsion Laboratory in the 1970s and ’80s, analyzing data from the Voyager 1 and 2 probes to Jupiter and Saturn. Sagan took Doyle under his wing, encouraging him to pursue his doctoral dissertation based on Voyager's data about Saturn's mysterious rings.

Sagan, who died in 1996, would have celebrated this new discovery, Doyle suspects. "Being Carl, I think he might have used the term 'elegant.' A whole new kind of anything (in this case a planetary system) is what Carl just loved."

Follow @CNNLightYears on Twitter

Post by:
Filed under: Eclipse • In Space • News
soundoff (670 Responses)
  1. Nicole

    I'd like , please http://ulungutur.beepworld.pl nude pre lolitas models ;yaeh the best ever!

    May 20, 2013 at 8:58 pm |
  2. Ainoa Castro

    Enhorabuena por tu ortografia. Un beso!

    April 15, 2013 at 1:50 pm |
  3. relevant resource site

    My partner and I absolutely love your blog and find nearly all of your post's to be just what I'm looking for. Does one offer guest writers to write content to suit your needs? I wouldn't mind composing a post or elaborating on a lot of the subjects you write in relation to here. Again, awesome site!| relevant resource site http://sdkfsdklfskdlflsd.com

    February 8, 2013 at 8:19 pm |
  4. http://greatestcompanyonearth.com/

    naturally like your web site but you need to take a look at the spelling on quite a few of your posts. Several of them are rife with spelling problems and I find it very troublesome to tell the reality however I will certainly come again again.

    July 14, 2012 at 12:15 pm |
  5. parking lot cleaning

    Hello there, You have performed an incredible job. I will definitely digg it and in my opinion suggest to my friends. I'm confident they'll be benefited from this website.

    April 6, 2012 at 8:06 am |
  6.       Vicodin dosage

    I know it was probably an oversight, but you might have wanted to note that you meant "closest planet to Earth outside of our solar system.       Vicodin dosageThe closest planet is venus, which at its closest is about 38 million km away.

    January 2, 2012 at 5:42 am |
  7. IGF 1 R3

    Matchless topic, it is very interesting to me )))) tHANKS lightyears.blogs.cnn.com tEAM

    December 2, 2011 at 8:37 am |
  8. Frederic Grinie

    Your work is very inspiring. This article is material that is absorbing and interesting. The points made here are original. I hope you continue this. Your work surpasses my expectations.

    November 30, 2011 at 11:32 am |
  9. outdoor lighting manufacturers canada

    I think other site owners should take this web site as an model – very clean and fantastic style and design, not to mention the content. You’re an expert in this area!

    November 23, 2011 at 5:53 am |
  10. Nona

    Hello everyone, amazing discovery a planet with TWO SUNS, which means double sunrise and double sunset. DID YOU KNOW THAT IT WAS MENTIONED IN THE QURAN HOLY, Suret Al-Rahman:
    Double sunrise and double sunset is also mentioned in the quran.

    رَبُّ الْمَشْرِقَيْنِ وَرَبُّ الْمَغْرِبَيْنِ 55:17
    Lord of the two sunrise and Lord of the two sunset 55:17

    Mashriq and maghrib are also used for sunrise and sun set respectively apart from its meaning of east and west
    فَأَخَذَتْهُمُ الصَّيْحَةُ مُشْرِقِينَ 15:73
    [Shakir 15:73] So the rumbling overtook them (while) entering upon the time of sunrise;

    September 20, 2011 at 4:44 pm |
  11. MikeSoq

    the force is strong within this planet

    September 17, 2011 at 12:56 pm |
  12. Rob

    I love it how they interviewed Santa Claus for this story... I can't see why, but it was a brilliant idea CNN!

    September 17, 2011 at 4:38 am |
  13. Bill Fitzgerald

    They seek not the Lord to establish his righteousness, but every man walketh in his own way, and after his own God, whose image is in the likeness of the world, and whose substance is that of an idol, which waxeth old and shall perish in Babylon, even Babylon the great which shall fall.

    September 16, 2011 at 11:12 pm |
  14. Bb

    Apologies for not following through with the messages above. We need to feel gratitude for the discoveries n understand the possibilities. Appreciate the minds who do the work and do take the time to learn about the wonders we have here n beyond.

    September 16, 2011 at 7:48 pm |
  15. rigpa1943

    After reading the comments of many news articles on CNN, and comparing those to the BBC and Duetchwelle News, I can only drop my head in shame, of how stupid American citizens really are. I am a U.S. citizen, and it seems at every article there are a group of readers who go off on aggressive tangents that have nothing to do with article at all. This is a public forum, don't say anything you wouldn't say in front of some else's face. Let's show a respect and class folks.

    September 16, 2011 at 5:59 pm |
  16. victoria

    it would be better if it was named Gallifrey

    September 16, 2011 at 4:30 pm |
  17. The Grammar Police

    This article and many of the posts above are using the word "sun" incorrectly. The sun only refers to the star in OUR planetary system. All other stars are stars. So it's impossible for a planet to orbit two suns. A common mistake in the English language, but a mistake is a mistake. Look up "sun" and "star" on Wikipedia for further clarification.

    September 16, 2011 at 3:35 pm |
    • fimeilleur

      The name of our star is Sol... not sun...

      September 16, 2011 at 11:27 pm |
  18. Wendu

    All this anger about the planet being named Tatooine and not being a desert planet but a gas giant is kind of pointless. The reason that scientists use names like this is to excite curiousity in the masses. How many of you would have clicked on the link to this story if it had been called "Kepler 16 planet has 2 suns." It's not going to grab people's attention like Tatooine.

    Why do people have to be such haters about Star Wars fans. It's a much better hobby than say drugs or unprotected sex. Jesus people calm down!

    September 16, 2011 at 2:55 pm |
  19. yahmez

    I wonder why I can`t read a scientific article without it being ruined by tea party and religious idiots. I take it you fools are no longer satisfied discussing birther and creationist nonsense. I hope we can continue to fund the space program, it gives me hope I will find a planet free of close minded jerks.

    September 16, 2011 at 2:27 pm |
    • whataboutbob

      dude i hope you're not going there with that attitude...geez most peeps here talking about how great it would be to meet E.T when you can't even stand the site of your neighbour and I'm not even talking about foreigners... hey a belief is exactly what it is, just that nothing less, so who cares what you or the next guy believe in, hey i believe i can fly, what's it to anyone as long as I'm not using you as wings, then it's all good b... btw your point makes a lot of sense religion is past belief, these peeps are just outright cuckoos...

      September 16, 2011 at 4:58 pm |
  20. BCJ

    Anyone remember the Sam Kinison bit? "Why don't they move to where THE FOOD IS!!!! YOU LIVE IN A $%#^ DESERT! NOTHING GROWS HERE! NOTHING'S GONNA GROW HERE! You know what this is? This is sand! You know what it's gonna be in a hundred years? IT'S GONNA BE SAND! Get your $#!^ together, we'l move you all in 1 trip!!"

    'Nuff Said.

    September 16, 2011 at 2:01 pm |
  21. El Pasoan1

    SPACE NERDS- Gotta love'em! If you get a job with these guys and you haven't watched Star Wars, then you're out of the club BUDDY!

    September 16, 2011 at 1:46 pm |
  22. whataboutbob

    Really, the same dude (ettes) who created the universe is the same who created God, so basically we're SOL, think about it, 1 day is like a thousand for God and vice versa, and science with it's light years, billions, and millions years of evolution, really, it's the perfect catch 22, none are disputable nor verifiable in any current human being lifetime, so just go and have fun and control what you can while you can and without doing at the expense of someone else if possible.....

    September 16, 2011 at 1:35 pm |
  23. chris

    a spaceship travelling at the speed of light would be there in no time, from the travellers point of view. That's because he is travelling with the speed of light riding on the event horizon. that is an important concept to understand, according to the theory of general relativity. to be precise, a spaceship could get infinitely close to the speed of light, but never reach it, which means there is a finite travel time, but it can be infinitely small. To the observer from earth, however, it would be about 200 years. So much to the scientific education of the author.

    September 16, 2011 at 12:27 pm |
  24. remy730

    Double sun all the way, across the sky, what does it mean? So intense. omg.

    September 16, 2011 at 12:20 pm |
  25. joel

    thats not a star, its a young planet

    September 16, 2011 at 11:35 am |
  26. curt

    From what I've read NASA already knew many solar system's have binary stars... That's why they leave the possibility open that our binary star maybe the planet X, we haven't found yet.. I think it's due back in 300 years.

    September 16, 2011 at 11:26 am |
    • curt

      according to Zecharia Sitchin planet x is due in about 300 years.

      September 16, 2011 at 11:27 am |
  27. Chuck Anziulewicz

    The article notes that "Getting to Tatooine aboard a spacecraft traveling at light speed – 186,282 miles per second – would take about two centuries." Actually THAT would be from the perspective of those of us back on Earth. But for anyone aboard the spacecraft, assuming it was indeed travelling AT the speed of light, the trip would be instantaneous.

    September 16, 2011 at 10:34 am |
    • Han the Man

      Except they would all have been crushed from the instant acceleration.

      September 16, 2011 at 11:10 am |
      • chris

        only the travel time at (close to) the speed of light would be (close to) instantaneous. The acceleration/deaccel does not have to be abrupt, of course. he just tried to explain the key point of general relativity.

        September 16, 2011 at 12:39 pm |
  28. Daniel

    Its funny how they say " Tatooine is not located in a galaxy far, far away, it's right in our own backyard – relatively – about 200 light years from Earth in the constellation Cygnus. UUMMMMM I don't think I have a back yard that takes 200 Light years to get there Just saying. In my opinion thats pretty far and it is in a galaxy far far away.

    September 16, 2011 at 10:29 am |
    • Han the Man

      Well seeing as how the galaxy is 100,000 light years across, there is no way this is in a far away galaxy.

      September 16, 2011 at 11:10 am |
  29. HAHAHA

    Observer, I can't get past the talking snakes either. Frankly it scares the you know what outta me. Now on the other hand my dog can talk. I don't mind that as much. It's really cute. Anyway, thankfully the membranes pinching em off scientific discovery has changed my stance and I won't have to deal with talking snakes.

    September 16, 2011 at 10:00 am |
  30. Odumbo

    Yes, oh Font of Wisom. But makes my Professor giggle.

    September 16, 2011 at 9:59 am |
  31. jason

    NASA scientists described the planet as a "wretched hive of scum and villainy."

    September 16, 2011 at 9:55 am |
  32. expert

    i always knew jedi were real

    September 16, 2011 at 9:47 am |
  33. Unobtanium

    The human race is living in a state of amnesia about the true
    origins of its past.
    Slowly all will be revealed.

    September 16, 2011 at 9:46 am |
  34. Henk

    What a bunch of Nasa and Cnn hype. This planet is nothing like tatooine since it`s a freaking Saturn size Gas GIANT. You can not walk on a gas giant. You can not live on a gas giant. And CNN ""accidentally"" leaves out this most important information about what kind of planet it actually is. BS. Again. No tatooine. Stop the lies. Just stop the lies.

    September 16, 2011 at 9:39 am |
    • Lucifer's Evil Twin

      Time to switch to decaf

      September 16, 2011 at 9:41 am |
    • Odumbo

      GAS GIANT? Sounds like my Bro.....

      September 16, 2011 at 9:46 am |
  35. freedomdem

    its not a second sun....its just in the early stages of formation and the PLANET closest to the sun has not cooled down enough yet.

    September 16, 2011 at 9:33 am |
  36. Han the Man

    Pffft 200 years? I could get there in 12 parsecs.

    September 16, 2011 at 9:25 am |
  37. Rudi

    love the scientist big ego..the claim that the know how the universe started….but barley know what is going on under there nose…..all the baloni that they feed us….why Albert Einstein was the greatest? Not because of his theories….because he was the most modest one…thanks wwwTheDimensionMachineDOTcom

    September 16, 2011 at 9:23 am |
  38. Katherine

    Kudos to Seti! we are not alone.

    September 16, 2011 at 8:51 am |
  39. reader

    The ability to find a planet with two suns is insignificant next to the power of the Force.

    September 16, 2011 at 8:51 am |
  40. Amanda

    I saw this press conference, and they were NOT calling it Tatooine. They made the comparison, jokingly, but when asked if it would receive a more "friendly" name than Kepler16b, they responded that if it was given a more informal name, it would probably be the media that did it. Either the author didn't bother to listen to the press conference, or just thought this made a much more interesting story.

    September 16, 2011 at 8:46 am |
  41. Zeta Reticulan

    You humans are getting warmer ...

    September 16, 2011 at 8:36 am |


    September 16, 2011 at 8:33 am |
    • Reality Check

      "..BUT I KNOW NOTHING SIGNIFICANT WOULD IN OUR TIME!" -What, are you like 2 yrs old?! At 48 there have been more space discoveries & achievments in my lifetime than I can count!

      September 16, 2011 at 8:42 am |
  43. Jason B.

    Great job on this discovery! Two things come to mind though. First: great, now Lucas has yet *another* reason to put out a "super-exclusive-real-color-of-the-twin-suns" edition of his movie. Second: too bad he'll probably sue them for using the word "Tatooine" as a nickname.

    September 16, 2011 at 8:31 am |
  44. BringOnTheSun

    I'm not much of a night person anyway

    September 16, 2011 at 8:26 am |
  45. TexanSwagger86

    For those who think researching these things are a waste of time... You dont know until you look. Who knows what we might discover. Anything is possible.

    September 16, 2011 at 8:25 am |
  46. Juan Tapia

    Well, George Lucas, just like Obama did. Show us a birth certificate (long-form), I'm sure it won't be from earth, your secret is out. You're from the Star Wars universe, that's why you're able to come up with such stories. LOL

    September 16, 2011 at 8:17 am |
  47. EinsteinWouldSlapYouAll

    Repeat after me, "Star Trek is NOT real." "Tatooine" is a cool piece of trivia, but means absolutely nothing to our planet. We can't go there. There's no food there for the starving. There's no water there to give to the thirsty. They can't fix our ozone layer, or replenish our oil reserves.

    It can't fix our wars or solve our political problems. It is, by all accounts, a meaningless piece of trivia that excites scientists in a theoretical sense ONLY. It has absolutely zero practical use or application to Earth.

    Again, repeat after me, "Star Wars isn't real." No, go back to your D&D games; the High Wizard has your invisibility cloak.

    September 16, 2011 at 8:05 am |
    • Dennis

      Yeah, stop everyone stop exercising your brains. The Koch Brothers will have new orders for you soon.

      September 16, 2011 at 8:07 am |
    • EinsteinWouldSlapYouAll

      I have no problems with PRACTICAL science. It cures diseases and makes food go farther. This isn't practical. It isn't useful. Give me one PRACTICAL use for this article and its information.

      September 16, 2011 at 8:09 am |
      • Steve

        Read about active pixel sensors. These are likely in your phone and were developed as seed research for the types of detectors used to do the imaging on spacecraft. Much of the technology that comes out of the space program has significant consumer satellite and defense applications. The actual scientific research is largely done by graduate students that make less than 20k/year.

        September 16, 2011 at 12:50 pm |
    • TexanSwagger86

      Thank you for making an a$$ of yourself. Im glad you think einstein helped develop the atomic bomb to help feed humankind and to discover more fossil fuel.

      September 16, 2011 at 8:21 am |
    • Amanda

      So, which isn't real? Star Trek or Star Wars? Just because something doesn't quickly provide an obvious benefit doesn't mean it's useless. How about quantum physics? You probably think it's useless people speculating about things to hard to see and very hard to imagine. Yet, you will be grateful for the technology if you ever need an MRI. Don't insult Einstein when you are unable to inform yourself beyond what you hear on the radio.

      September 16, 2011 at 8:51 am |
  48. CT

    Obama says if we can get the Russians to fly our 500million in solar panels to location with a very long extension cord.....we could save the world!!! Brilliant idea sir, we should invest everything we have left.

    September 16, 2011 at 8:05 am |
  49. Veganlicious

    Awesome!! When can I start my moisture farm?

    September 16, 2011 at 8:04 am |
  50. manny


    September 16, 2011 at 8:01 am |
  51. Cliff

    In other news...Michele Bachmann has come out against the planet, saying, "this is clearly the work of the devil, a sort of bondage, something our founding fathers, men like Issac Newton, would be against." Rick Perry, also issued a statement, saying, "this is not part of the natural plan, so I don't accept this so-called 'science' – it's another hoax concocted by liberals to drum up more research money for liberal universities."

    September 16, 2011 at 7:59 am |
  52. j

    Scientists are truly morons...instead of calling it Tatooine, they give it an official "scientific" name...

    Wasted education...

    September 16, 2011 at 7:57 am |
  53. yourbeliefsdontchangereality

    If there was a race of beings in that solar system and they had a religion whose book contained the line "And God made two great lights; the greater light to rule the day, and the lesser light to rule the night" (Genesis 1:16) then the atheists of that race of beings could not use that specific verse as proof of the falsity of scripture. We, however, can, as our star system contains only 1 light source, and the moon simply reflects light. In b4 all the apologists say that "reflection" counts, or is what the "Word" meant to say.

    September 16, 2011 at 7:57 am |
    • TexanSwagger86

      Amen. True that. True that.

      September 16, 2011 at 8:02 am |
  54. brian

    not surprisingly, the planet's name is is on rick perry's drivers license...

    September 16, 2011 at 7:55 am |
  55. Tony

    When I heard about this, I wondered if the planet followed a figure eight trajectory. More interesting, but it's great that this has been confirmed.

    September 16, 2011 at 7:55 am |
  56. Stephen

    It doesn't matter if there are two suns. The Obama administration decided to invest in solar panel companies that went bankrupt.

    September 16, 2011 at 7:52 am |
    • Dennis

      and I thought he was investing in America's Energy Future.

      September 16, 2011 at 8:05 am |
    • lol

      i love idiots who bring politics into this...it just shows how stupid you are

      September 16, 2011 at 8:41 am |
  57. Dennis

    A star that is about 200 light years away, would take about two centuries to get to at the speed of light?

    Oh, the redundancy!

    September 16, 2011 at 7:51 am |
    • gh

      It would also take 20 decades! Or, 1/5 of a millenia!

      September 16, 2011 at 7:55 am |
  58. Steve

    Well considering the universe is accelerating it's expansion, and is always expanding in every direction, the entire story of Star Wars could exist somewhere.

    September 16, 2011 at 7:49 am |
1 2 3


  • Elizabeth Landau
  • Sophia Dengo
    Senior Designer