Cosmology News

Medium size worlds upset “Earth is not unique” planet modelling

Spread the love

In “Super-Earths give theorists a super headache” (Nature, 13 December 2011), Eric hand reports, “An abundance of medium-sized worlds is challenging planet-formation models.”:

By now, it’s not surprising that NASA’s Kepler space telescope is turning up extrasolar planets by the bushel. Last week, at the first Kepler science conference at NASA’s Ames Research Center in Moffett Field, California, mission scientists announced that the space telescope has identified 2,326 candidate planets, nearly doubling its haul since February.

But what has puzzled observers and theorists so far is the high proportion of planets — roughly one-third to one-half — that are bigger than Earth but smaller than Neptune. These ‘super-Earths’ are emerging as a new category of planet — and they could be the most numerous of all (see ‘Super-Earths rising’). Their very existence upsets conventional models of planetary formation and, furthermore, most of them are in tight orbits around their host star, precisely where the modellers say they shouldn’t be.

Shouldn’t be? If our Earth is just another planet, then they shouldn’t be in those tight orbits. Otherwise, so what?

10 Replies to “Medium size worlds upset “Earth is not unique” planet modelling

  1. 1
    Grunty says:

    “If our Earth is just another planet, then they shouldn’t be in those tight orbits.”

    This just means that our models didn’t predict planets in tight orbits about their sun. As the article states, they expect to refine the model to be able to account for it. It does not mean that we will not find Earth-sized planets in Earth-sized orbits. Are you concerned that the Privileged Planet will tur out not to be so privileged after all? Perhaps even in the next few months, when the next batches of results from the Kepler Objects of Interest list will be released?

  2. 2
    Bantay says:

    If a discovered exoplanet doesnt have ALL the amazingly fine-tuned parameters (for intelligent life), then it’s not “earth-like”. Thus, “super-earths” is not an honest representation of what is being discovered in cases where the term is used.

  3. 3
    Jon Garvey says:

    The real question is what happens if they find Earth II, 700 light years away. Presumably they focus in and find CFCs or 747 exhaust in the atmosphere, and rejoice greatly.

    Then what?

  4. 4
    Joe says:

    Laser messenging! Sure it will take 700 years to get the message there…. 🙂

  5. 5
    Jon Garvey says:

    “Thank you for your call. This is a recorded message. We regret to inform you that our species became extinct 1000 years ago, but please leave your name and number and someone will get back to you. Meanwhile, if you keep trusting in God, and love one another, you’ll never be alone.”

  6. 6
    markf says:

    The article explains that if current models of planetary formation are true then there shouldn’t be such a large proportion of planets of this size and they shouldn’t be in such tight orbits. So there is some evidence against that model of planetary formation. How on earth do you jump from that to

    If our Earth is just another planet, then they shouldn’t be in those tight orbits. Otherwise, so what?

  7. 7
    Joe says:

    1400 years later, back on earth:

    “Sir we just received a reply to our message from 1400 years ago- it says their civilization stinks for 1000 years and to leave it to God because they want to be alone.”

  8. 8
    woodford says:

    Markf – that was exactly what I was wondering too. Why is with so many of the “News” articles here that the address on the package rarely matches the contents of the package. Is this what passes for journalism around here?

  9. 9
    champignon says:

    Exoplanets are around every star, study suggests

    Every star twinkling in the night sky plays host to at least one planet, a new study suggests.

    That implies there are some 10 billion Earth-sized planets in our galaxy.

  10. 10
    Joe says:

    Umm earth-sized does not mean earth-like- We still have a privileged status.

Leave a Reply