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New Exoplanet Circles Star in Less Than 9 Hours (and Is Covered by Molten Lava)

This artist illustration shows the newly discovered exoplanet Kepler 78b sorbiting so close to its parent star that a single year lasts only 8.5 hours. Credit: Cristina Sanchis Ojeda
This artist illustration shows the newly discovered exoplanet Kepler 78b orbiting so close to its parent star that a single year lasts only 8.5 hours. Credit: Cristina Sanchis Ojeda

NASA’s Kepler Space Telescope has helped discover a new Earth-sized planet that has a year that lasts less time than an average work day or a good night’s sleep.

Kepler 78b zips around its host star in a mere 8.5 hours — making this one of the shortest orbital periods ever detected. (See also: “Most Earthlike Planets Found Yet: A ‘Breakthrough.'”)

Researchers at MIT are reporting that Kepler 78b sits about 700 light years away from Earth, and orbits about 40 times closer to its parent star than Mercury does.  This scorched planet orbits so close  that it sports temperatures reaching up to 5,000 degrees Fahrenheit.

While this would seem to be the destination to celebrate a lot of birthdays it’s probably not the best place for a vacation since scientists predict the surface is covered with molten lava.

“We’ve gotten used to planets having orbits of a few days,” said Josh Winn, co-author of both studies in a press statement.

“But we wondered, what about a few hours? Is that even possible? And sure enough, there are some out there.”

Winn and his team were able to detect the light given off by Kepler 78b by measuring the dips in starlight each time the planet periodically passed in front of its star. (Related: Kepler Spacecraft Disabled; “Exciting Discoveries” Still to Come)

Looking forward, Winn will be working towards getting a handle on how much this planet may actually tug on its star, which will hopefully allow the team to measure the planet’s mass, making it the first Earth-sized planet outside our own solar system whose mass is known.

But the discovery of this hellish planet doesn’t rule out the possibility that there may be other short-period alien worlds out there that are indeed habitable. Winn’s team is on the hunt now for just these kind of planets circling small brown dwarf stars.

“If you’re around one of those brown dwarfs, then you can get as close in as just a few days,” explained Winn. “It would still be habitable, at the right temperature.”

The discovery of Kepler 78b appears in The Astrophysical Journal.

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  1. Mugume Abraham
    August 30, 2013, 5:41 am

    Looking out through space is nice but where does it stop .like how many light years someone give me an answer

  2. tee
    August 23, 2013, 11:27 pm

    Amazing! So how long is a day there….maybe some seconds. Wow!

  3. Alao Ibukun
    August 23, 2013, 4:51 pm

    Science is really stretching beyond the limits of impossibility

  4. Darren
    August 23, 2013, 4:23 am

    Cool, blazing fast

  5. Markus H
    August 23, 2013, 12:12 am

    I am READY!

  6. Dileep V. Sathe
    Pune / MH / India
    August 22, 2013, 10:41 pm

    It would be interesting / essential to know if the orbital velocity of Kepler 78b is in accordance with our famous equation: square of velocity = GM / R

  7. Greg
    Londonderry, NH
    August 21, 2013, 3:47 pm

    I wonder if this is what is left of a gas giant after it had it’s atmosphere boiled off. I guess this answers the question of how close a planet can get without falling in. It is hard to imagine a mechanism that allows one to get this close and no closer. I imagine that the star is a fairy quiet on with regards to flare activity.

  8. The Follower of 78b
    Hays High
    August 21, 2013, 11:59 am

    That is SO aweosme

  9. The Follower of 78b
    Hays High
    August 21, 2013, 11:58 am

    Wow that is extremely awesome

  10. Yummy
    August 21, 2013, 11:56 am

    So maybe everything we human can imagine, is all our there

  11. Tegar
    August 21, 2013, 11:48 am

    hmm…reminds me about Planet “New Folsom” in StarCraft

  12. anthony gutierrez
    quezon city,NCR, Phillipines
    August 21, 2013, 4:06 am

    what next exploration in outer space?

  13. Britnney
    New York City
    August 21, 2013, 3:44 am

    Oooh It would be nice to know all the facts on this exoplanet

  14. dennis
    memphis, tn.
    August 21, 2013, 1:15 am


  15. Pranil Chandra
    August 20, 2013, 10:17 pm

    If you’re going to quote astronomical numbers, please use metric. It’s far more more ‘universal’ than imperial units.

  16. Aleksi
    August 20, 2013, 6:07 pm

    Can this get for finnish ? 🙂

  17. Tracy
    August 20, 2013, 5:54 pm

    “So sorry i was late for work,I woke up late and only had 30 years to get here.”lol

  18. Daniella
    August 20, 2013, 5:17 pm

    Is its year shorter than its day?