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Center for Exoplanets and Habitable Worlds (news of improved instrumentation)

  1. Oct 2, 2008 #1


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    Steinn Sigurdsson reports on sensitivity of new planet-search instruments, how slow a wobble can they pick up?

    If they can see the central body wobble at a speed of only 1 meter/second then they can pick up lower-mass planets, more earthlike planets going in more earthlike orbits, than if they can only see 10 meter/second wobble.

    At the rate sensitivity is improving they project being about to detect earthlike things by 2010 or 2011. Sounds wonderful, I hope the goal is reached that soon!

    they had a meeting of a new group.

    http://scienceblogs.com/catdynamics/2008/10/pending_planets.php [Broken]

    Steinn says that at the meeting they flashed something preliminary from COROT collaboration about finding an interesting planet, we will hear more about this.
    the preliminary unconfirmed news as I interpret what he says is

    radius < 2 X earth radius (unsure as to what Steinn is saying)

    mass = 2 to 8 X earth mass.

    composition rocky or icy, maybe liquid water as well (Steinn indicates)
    I don't know the luminosity of the star so I can't guess the temperature.

    COROT is a european (ESA) spacecraft which is able to detect TRANSITS of planet across the face of the star by the dip in the lightcurve.
    one tells how big the planet is by how much starlight it blocks, while it is in transit.

    here is the quote from Catdynamics:
    ...The hopefully-soon-to-be-published COROT detection-that-is-extremely-interesting was flashed up on the screen.

    The radius is clearly less than 2 earth radii, and (radial velocity?) confirmation is being pursued. One infers a mass of at least 2 earth masses and no more than 8 earth masses or so. Depends a bit on what one believes about theoretical predictions of phase transitions at very high pressures and abundance of ice VII, X and XI. Or so I am told.
    Hence one also infers it cannot be a neptunian, but must be a true rocky or icy planet (well, melted ice...).

    Interesting... COROT clearly has the sensitivity so where are the other candidates?
    Could be they have issue with systemic calibration over long time periods???
    Which means a lot of candidate small planets may pop out of the data if and when they sort that out.
    I expect a lot more from COROT, but they may take their time and do it properly, especially if there is concern about systematics in the relative photometry. The short term relative photometry looks exquisite. ..

    Last edited by a moderator: May 3, 2017
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  3. Oct 6, 2008 #2


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    That is very exciting marcus. Shortly after that 2010-11 time frame there is hope that we will be able to detect tell tale signs of life on planets by directly imaging them in the mid-infrared region. The DARWIN exoplanet mission uses nulling interferometry to cancel out the parent stars light. DARWIN is set to launch currently in around 2015.

    Here is the web site for those interested.

    Last edited by a moderator: Apr 23, 2017
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