Kepler: All systems go!


20 Responses to “Kepler: All systems go!”

  1. Mark Dow says:

    How could it be that six planets can be formed and/or maintained at an orbit smaller than that of Jupiter (Kepler 11)? Does this likely impact the nebular hypothesis, or are there other models of planet formation that might be needed?

    Speculation, please.

    • Mark Dow says:


      “five planets … orbit smaller than that of Mercury”

    • spriggan says:

      To paraphrase the late great Rick James, “Gravity’s a helluva drug.”

    • travtastic says:

      Well, if they have weird and disparate compositions, they could conceivably be captures, but that’s highly unlikely. They could have just formed there. I’d day the most likely answer is inward migration from gravitationally interacting with each other.

    • Spaceman Dave says:

      One of the big findings of modern planet formation research is just how much planets move around during formation. There are several well-studied migration mechanisms: Actually, one of the big problems is getting planets to *stop* moving around.

      I am currently studying planetesimal-driven migration as it may have applied to the formation of rocky planets. It’s likely that the Kepler-11 system experienced some form of planet migration, although our understanding of all the physics involved is still relatively incomplete. More observations like Kepler’s will help inform and constrain models, as will future observations. For instance, the ALMA observatory ( ) will give us lots of information on the structure of planet-formation disks around young stars at very high resolution. This is indeed a very exciting time to be involved in this kind or research.

  2. Anonymous says:

    This is great news! And this is only the beginning…

  3. Mark Dow says:

    Something new under a sun, Kepler 11:

    • Anonymous says:

      “The thing that hath been, it is that which shall be; and that which is done is that which shall be done: and there is no new thing under the sun.” Ecclesiastics 1:9

  4. RebNachum says:

    Look at those planets. Just look at them.

  5. Anonymous says:

    Some of these planets have very short rotations around there star i wonder what there night sky looks like? While i know the rotation of a planet is one way the stars move across the sky the rotaion around the star is another.

    Would streaks of light in the sky be considered stars if anyone was to view them?

  6. thebelgianpanda says:

    This is seriously one of the coolest things I’ve heard in a very long time. Remember a few short years ago when there wasn’t direct proof of any exoplanets?

  7. TimDrew says:

    All I can say is: I’m happy to be living in this Time.

  8. Anonymous says:

    Greeks weren’t the first to theorize atoms and other planets. This was written in Srimad Bhavatam and Mahabarata written by Sage Vyasadeva in ancient India beore the greeks. Check out Hindu Cosmology, they already know all of this.

    • Ito Kagehisa says:

      Yeah, but again, the atoms of the ancient Hindus didn’t bear a very strong resemblance to those of Rutherford and Bohr. The ancient Greek and ancient Indian atomic theories were impressively brilliant from a philosophical and logical perspective, but really have more to do with epistemology and theology than with physics.

      When you are arguing that wood must be a compound substance because it contains atoms of fire that can be liberated by ignition (or that meat is a compound substance because it spontaneously generates maggots) you are pretty far away from valence shell calculations. It’s still impressive, but it does not subtract any primacy from more recent atomic theorists.

  9. Ito Kagehisa says:

    Space telescopes = awesome!

    But I’ve got a copy of Lucretius here, and I don’t think the atoms he’s talking about bear much resemblance to the atoms of Rutherford and Bohr. The ancestry is there, only about as tenous as Clerk Maxwell’s relationship to Unix daemons if you ask me.

  10. Anonymous says:

    How long before we observe planets collide?

  11. hassenpfeffer says:

    Don’t forget Giordano Bruno when discussing the history of human thinking about atoms and infinite space.

  12. turn_self_off says:

    We really need to crack the FTL drive nut soon!

  13. Jesse M. says:

    Any word on which stars those five Earth-range planets in habitable zones are orbiting? Would be interesting to know if they’re all smaller stars than the Sun (smaller stars are actually more long-lived, right?), and for sci-fi fantasy purposes would also be interesting to know how far away they are from us.

    • Lee Billings says:

      Hi Jesse,

      If I’m interpreting things correctly, all of the five HZ-orbiting *candidates* that are estimated to be twice the size of Earth or smaller are orbiting stars smaller than the Sun. Otherwise, we wouldn’t be seeing them yet in the data. Generally speaking, the Kepler team wants three transits of an object to be sure it’s legit. For a star like our Sun, something at Earth’s location in the habitable zone orbits with a period of a year. So we won’t be seeing any of those puppies til 2012, it seems. Smaller stars are cooler and less radiant, so their habitable zones are closer in, meaning that objects there have faster orbits. So they make three circuits faster than HZ-planets around larger, hotter stars.

      All the stars are very far away, and very dim too. IIRC, the stars for the two most promising candidates each have an apparent magnitude of 12-something, which is pretty faint.

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