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Posted by: Tom Womack May 3 2007, 02:20 PM

http://news.bbc.co.uk/1/hi/sci/tech/6611557.stm

is reporting that Corot has found its first planet. I can't find an arxiv paper about this, or even a press release, but there are many here better at squirreling out data releases than me.

1.3Mj, 1.8Rj so it's a very inflated planet, 1.5-day orbit around a 'star quite similar to the Sun' might account for that. In the Monoceros field (Corot is now pointing at the Scutum/Aquila field).

Posted by: ustrax May 3 2007, 04:53 PM

Here's ESA's rhttp://www.esa.int/esaCP/SEMCKNU681F_index_0.html.

Posted by: Sunspot May 3 2007, 04:54 PM

And according to this New Scientist article COROT could be up to 30 times more sensitive than it's original design specification.

http://space.newscientist.com/article/mg19426023.800-european-planet-hunters-on-brink-of-earthsized-prize.html

Posted by: AlexBlackwell May 3 2007, 06:38 PM

Emily has a http://www.planetary.org/blog/article/00000960/. Also, I'm not sure if it's mentioned here or not, but there is a new, related paper in press with Icarus:

Could we identify hot Ocean-Planets with CoRoT, Kepler and Doppler velocimetry?
Icarus, In Press, Accepted Manuscript, Available online 1 May 2007,
F. Selsis, B. Chazelas, P. Bordé, M. Ollivier, F. Brachet, M. Decaudin, F. Bouchy, D. Ehrenreich, J.-M. Grießmeier, H. Lammer, et al.
http://arxiv.org/ftp/astro-ph/papers/0701/0701608.pdf

Posted by: Rakhir May 3 2007, 09:11 PM

And the CNES release (in French).
http://www.cnes.fr/web/5891-corot-decouvre-sa-premiere-exoplanete-.php

Posted by: stevesliva May 3 2007, 10:05 PM

I've been wondering, is there any reason to think that the orbital planes of other solar systems [in specific directions] will be aligned in such a way that we'll see more eclipses than total randomness would dictate?

Are there going to be tantalizing glimpses of transits that don't reoccur within reasonable timeframes?

Posted by: Tom Womack May 4 2007, 10:58 AM

The Corot photometry is wonderfully stable, and looks as if it can pick up eclipses on a single occurrence rather than having to do a phased integral; Jupiter's diameter is 1/10 of the Sun, so a Jupiter transit would be a 1% drop in light, which Corot would pick up very happily, It would last (I think) jupiter_orbital_period * (sun_diameter / 2*pi*jupiter_orbit_diameter) = 4330 days * 1.4e6 km / (6.28 * 778e6km) = 1.25 days.

I don't think there's much that dims a star in a spectrally-uniform way with a flat bottom and that kind of ingress and egress period, so you would really see it in the data. I don't know how long Corot will last, it's working in the optical spectrum so doesn't have cryogens to exhaust, and it doesn't have to do very complicated station-keeping so the fuel should last reasonably, but two Jupiter-years is maybe a little long to expect, and the cadence where it looks at Monocerus for six months and Scutum for six months starts to be troublesome at the longer periods.

I'm looking forward to seeing the low-mass and long-period bits of phase space get populated, and to hearing complaints that there's not enough high-resolution-spectrograph time available to follow up all the transit detections!

Posted by: Greg Hullender May 4 2007, 07:32 PM

Steve: The Kepler guys figure about 1/2 percent of stars with planets will be aligned enough for us to see transits -- assuming random alignment.

http://kepler.nasa.gov/sci/basis/character.html

Wikipedia claims 10%, but in this case I think I know whom to believe.

http://en.wikipedia.org/wiki/Methods_of_detecting_extrasolar_planets#Transit_method

I've also wondered whether this will REALLY be random, but I note that so far very few observed planets are transiting -- no surprise given only 200-odd extrasolar planets so far.

So I guess we can say that, if it's not random, it's not hugely skewed either.

I note also that Kepler claims they can detect Jovian-sized transits from a single event; it's only for Earth-sized transits that it needs to see three events to be sure.

--Greg

Posted by: Jyril May 5 2007, 12:08 AM

10% claim should be true in the case of hot Jupiters. For more distantly orbiting planets, the value is of course considerably lower.

"Planets with small orbits" says Wikipedia so it's apparently correct if not clear.

Posted by: Olvegg May 5 2007, 10:08 AM

0.5% is for Earth-like orbits around Sun-like stars.

Posted by: stevesliva May 7 2007, 11:07 PM

Interesting. Hopefully Kepler prospers for a good many many years then!

Also that 0.5% figure is both plenty high, yet depressing in the regard that 99.5% will still be hidden from this technique. But it's no doubt conservative. I again wonder how many "near misses" will be detectable. Should be great to see.

Posted by: Greg Hullender May 9 2007, 03:04 AM

Steve: What is more interesting about the 0.5% number is that it is independent of the distance of the star; at first it would seem that the further away it is, the less likely a planet is to be lined up so as to transit, but it turns out this is not the case. (Play with the geometry a bit and see.)

Of course the further away a star is, the harder it will be to tell that there was a transit; geometry can't fix that!

--Greg

Posted by: edstrick May 9 2007, 08:27 AM

The fundamental purpose of missions like Corot and Keplar (and "Ogle" type searches for lensing events as well as whatever transits they catch) is to establish the statistical patterns of planetary system occurrence.

Star: 1) What mass stars, 2) what metallicity stars 3) what environment stars (disk, halo, globulars.. ) 4) what age stars. (yes. the last 3 are all significantly correlated)

Planet: Mass, Diameter, thus (density and gross composition)

Orbit: Toasty, close, distant, eccentric vs circular.

Before we build EITHER of the Terrestrial Planet Finder mission, we need a good model of how many there will be of what sizes -- around what mass and metallicity stars -- in what orbits -- in the solar neighborhood.

If we design and fly an inadequate TPF and find 3 barely-quasi-terrestrial planets for a budget of 3 billion dollars. Uh.......

If we know a 1.5 billion dollar TPF will find 2 or 3 dozen substantially terrestrialish planets (.8 to 1.5 earth mass, similar stellar insolation), it may fly a lot sooner than that 3 billion doller mission.

And... even though we'll not see a good spectrum or hardly anything from most terrestrial size or so planets Keplar and Corot may find, we'll get fabulous understanding of the population of planets out there and the type of planetary systems they are part of that we only half or quarter get from the doppler surveys.

Posted by: Mongo May 9 2007, 01:28 PM

Are you sure about this? The width of the 'band' of sky that can see a transit is the same width as the diameter of the primary as seen from the planet, hence a planet twice as close as another will be visible as transiting from twice the area of sky. The 0.5% number comes from the fact that a planet in a habitable orbit should have its primary subtend about 0.5 degree -- which actually suggests that its transit should be visible from about 0.44% of the sky. A planet ten times closer would have its primary subtend about 5%, so its transit would be visible over about 4.4% of the sky, and so on.

Bill

Posted by: Greg Hullender May 9 2007, 11:44 PM

Mongo: You're correct, if "distance of the star" means "from the exoplanet," but I meant "from Earth." A star 50 light years away is (all other things being equal) just as likely as one 5 light years away to have a transiting planet. Maybe that's obvious, but it surprised me at first.

--Greg

Posted by: ustrax May 14 2007, 09:53 AM

"...eclipses that can be detected are “shallower and thus the planets detectable are going to be smaller. If the periods are short enough so that we can see enough eclipses for a given planet (a process called epoch-folding) we are going to be so sensitive that we could see one earth-radii planets.”

From a quick update with Malcolm Fridlund at http://spaceurope.blogspot.com/2007/05/corot-140507-update-with-malcolm.html.

Posted by: Jyril May 14 2007, 04:38 PM

According to the http://spaceurope.blogspot.com/2007/05/corot-140507-update-with-malcolm.html COROT's sensitivity may be just enough to detect reflected light from an extrasolar planet's surface in a similar manner Spitzer has done... but instead of infrared, it observes in the visible light.

Posted by: tacitus Jul 25 2007, 05:16 PM

Anyone know when the COROT guys are going to make their next announcement? Any rumors yet?

Their first was a wonderful tease...

Posted by: Rakhir Jul 25 2007, 08:26 PM

A small update was posted yesterday on the CNES website.
http://smsc.cnes.fr/COROT/GP_actualite.htm#juil2007a

Posted by: Del Palmer Jul 26 2007, 02:33 AM

Interesting; thanks for posting this. Spitzer has done both emission and absorption, but reflection?! I guess they must be using IRAC 3.6 microns, as the longer wavelength bands will be swamped by intrinsic emission from the planet. Oh boy, that would be quite an achievement if they can do it. I would hate to be the sucker PI reducing the data for that observation.

Posted by: tacitus Jul 26 2007, 02:47 AM

Thanks for pointing out the update, Rakhir.

Now, I assume they mean 12,000 light curves from stars that are candidates for hosting exoplanets. 12,000 light curves involving exoplanets in one month would be utterly mind blowing.

Not helping with the anticipation...

Posted by: nprev Jul 26 2007, 03:48 AM

Oh, no, not at all! Doesn't sound beyond the pale, though. We really are on the verge of finding out whether planets are more plentiful than stars, if that is indeed the case...the smart money's always been on 'yes'. Mach's Principle may yet prove to be far more powerful than we realize at the local level, although in a quantitative, not qualitative sense...

Posted by: ustrax Jul 26 2007, 09:10 AM

Thanks for the update Rakhir.
tacitus,
Here's what I got from Dr. Fridlund (ESA COROT Project Scientist) some days ago, when it was announced the http://spaceurope.blogspot.com/2007/07/hd-189733b-first-of-kind-with-giovanna.html:
"COROT is progressing according to plan. There will not be any new announcements before we have had time to write a few papers and submit them to the journals so with vacations you are talking about at least 3 months.
We have a lot of exo-candidates that we are beginning to follow up from the ground (I was myself in Tenerife last week and observed one of them). But as I said above it will be some time."

Posted by: nprev Jul 26 2007, 09:37 PM

Man...I'm trying to contain irrational exuberance, but boy oh boy oh boy...we might just actually know a thing or two in detail--FINALLY--about how things really are around other stars after all the novels and stories, even sans starships, in a few short years!

Posted by: Jyril Jul 26 2007, 10:16 PM

Well, the negative side of the COROT survey is that the search is limited to closely orbiting transiting planets so we get a very biased sample. Which is far better than nothing, of course.

A microlensing planet survey equipped even with a relatively small telescope could find Earth-mass or smaller planets in any orbital distance (including free-floating terrestrial planets)! It could detect every planet of the Solar System except Mercury, which is not massive enough and orbits too close the Sun. The obvious downside is of course that the lensing events are unique and no physical properties of the planets can be studied. But it could give a good sample of planets around very different kinds of stars.

Posted by: remcook Jul 27 2007, 09:19 AM

I'm wondering...what would be required for such a "gravity lensing" mission? Could COROT not search for such events (change in radiance of microlensing instead of small dips by transit)?

Posted by: cndwrld Jul 27 2007, 11:14 AM

This isn't related to Corot, but it may be of interest to people who are interested in Corot. Venus Express is taking observations of Earth, from Venus, using the Virtis and Spicav spectrometers. The idea is to try and gather a data point regarding what a habitable planet would look like from a distance. Once the technology is available, observations like this may give an idea of what would be best to look for.

Several of these observations have been taken, with more scheduled. It is a low priority thing, and I have no idea when any results may come out of it, but it is an interesting idea and some observation time is being dedicated to it.

Posted by: belleraphon1 Aug 16 2007, 04:34 PM

All planet lovers

COROT update may be coming next week during the European Planetary Science Conference - August 20-24th.

http://meetings.copernicus.org/epsc2007/annotation.html

COROT abstract
http://www.cosis.net/abstracts/EPSC2007/00316/EPSC2007-J-00316-1.pdf

Craig

Posted by: djellison Aug 20 2007, 09:28 AM

http://www.planetary.org/blog/article/00001089/

That's about it - it was more 'CoRoT will be great when we get our ground software finished' than 'Look - Exo-Earth's!'

Doug

Posted by: belleraphon1 Aug 20 2007, 11:31 AM

Thanks Doug!!

I suspect they are going to keep things pretty close to their chests for a while.... but still an interesring report. And a teaser for what is to come.

Craig

Posted by: djellison Aug 20 2007, 01:51 PM

I think they just want to be 100% sure on REALLY interesting things with follow-up ground based obs with spectroscopy before going "WE FOUND AN EARTH"

Doug

Posted by: belleraphon1 Aug 20 2007, 03:53 PM

Yes, they certainly need to be prudent.

What I am reading sounds very promising as far as what COROT is capable of. Much to look forward to.

Thanks Again Doug.

Posted by: nprev Aug 21 2007, 03:37 AM

Yeah...to quote Carl, "Extraordinary claims require extraordinary evidence." Seems that the COROT team is employing this invaluable heuristic, and should be commended for doing so...but, boy howdy, I sure hope that there's something extraordinary just around the corner...

Posted by: JRehling Aug 21 2007, 07:04 PM

Check my math in trying to characterize the bias.

Given two similar planets orbiting two similar stars, but with one planet N times farther from its star than the other, the ratio of likelihood of detection in a short time frame should be N^2.5. That is, the probability of appropriate geometry for a transit is decreased by N for the farther planet, whereas the probability of a transit taking place at the right time is a function of the orbital period, which introduces another factor of N^1.5.

For example, if Earth were orbiting at 5 AU, it would be precisely 1/5 as likely for its orbit to transit the Sun as seen from afar, and if it did, it would do so about 1/11th as often. So a factor of 5 in distance translates to a factor of 55 in transit observations. A factor of 10 in distance translates to a factor of 300 in transit observations.

The temporal factor is mitigated as the observations continue. Given a mission lasting Y years, we'd get one observation of every transiting planet with a period <=Y, two observations of every transiting planet with a period <=Y/2, and a probability Y/X of one observation of every transiting planet with a period X longer than Y.

The diameter of the planet is also a minor factor. Jupiter might graze the Sun's disk whereas a Pluto in the same location would just miss. As the planets get much smaller than the star, this factor almost vanishes.

COROT will survey a few different areas, none for more than 150 days or so, so repeat detections will be strictly limited to planets in close-in orbits. Single detections of planets farther out will (presumably!) take place, and could help us get an idea of the distribution of planets in different-sized orbits. But at some point out there, the data will be too sparse to make predictions significant.

So overall, I think it's going to be pretty sparing in telling us about the raw numbers of Venuses, Earths, and Neptunes. But a few data points would be a lot nicer than none.

Posted by: Greg Hullender Aug 22 2007, 03:26 PM

I get the same result, JR.

A good question would be "how many transits do they need to see to confirm a discovery?" On the Kepler site, they say they'll only need one for Jovian planets (although obviously you need two to get the orbital period), but that for Earth-sized planets, they want to see three transits.

If COROT switches targets every few months, that'd mean it really wouldn't spot any Terrestrial planets with periods longer than a few weeks. That'd still be very interesting, but makes it seem unlikly they'll find anything that could fairly be described as "another Earth."

--Greg

Posted by: nprev Aug 22 2007, 03:59 PM

Just out of curiosity, would the habitable zone of a fairly anemic red dwarf be close-in enough for a period of a few days to be possible for "another Earth?"

Posted by: stevesliva Aug 22 2007, 05:38 PM

Wouldn't something that close be tidally locked?

Posted by: Greg Hullender Aug 22 2007, 07:42 PM

Tidal locking time is an interesting problem.

http://en.wikipedia.org/wiki/Tidal_locking

Considering the warning that these figures can be off by a factor of 10, I get the following for putting an Earth with a 12-hour day to start with around some familiar stars:

Sol: 365.25 day period, 5.4 billion years to tidally lock. (Ignoring the effect of the moon).
Alpha Centauri A: 524-day year, 16 billion years (Earth years) to lock.
Tau Ceti: 221-day year, 1.7 billion years
Alpha Centauri B: 207-day year, 800 million years
Epsilon Eridani: 134-day year, 170 million years
Gliese 581: 7.8-day year, 120,000 years.
Proxima Centauri: 3.9-hour year, 350 days.

The difference between Tau Ceti and Epsilon Eridani surprises me; I hadn't realized there was almost a factor of two luminosity difference, even though the latter is actually slightly more massive.

Anyway, even with all the caveats, it seems to be a cinch that any earthlike planet with a period under 100 days will be tidally-locked.

(Anyone want to check the math?)

--Greg

Posted by: belleraphon1 Aug 23 2007, 12:46 AM

So what if it is tidally locked?

http://www.liebertonline.com/doi/abs/10.1089/ast.2006.0124

http://www.astrobio.net/news/article1694.html

Craig

Posted by: stevesliva Aug 23 2007, 01:49 AM

Iiiiinteresting. I wonder what the climate models predict for temperature maps on the sun-facing side?

I also find it interesting that the earth would be tidally locked in a mere 5 billion years sans luna.

Posted by: Greg Hullender Aug 23 2007, 06:03 AM

Remember that there's enough fudge in these numbers that it might really be 50 billion, not 5 billion. Thing is, the effect of radius (a SIXTH power!) is so strong and the ages of these systems is so great (billions of years, typically) that it doesn't really matter. Anything with an estimate under ten million years was almost certainly tidally locked long, long ago -- even those with estimates under 100 million.

It's interesting to note that Luna makes the moment of inertia of the system over 100 times larger, so that'd probably push that number up to 500 billion years, although that wouldn't rule out Earth being tidally locked to the moon well before that happened.

--Greg (The other major caveat is that this equation came from Wikipedia -- I didn't derive it myself.) :-)

Posted by: belleraphon1 Aug 23 2007, 12:44 PM

"Simulations of the Atmospheres of Synchronously Rotating Terrestrial
Planets Orbiting M Dwarfs: Conditions for Atmospheric Collapse and
the Implications for Habitability"
http://www.seismo.unr.edu/ftp/pub/gillett/joshi.pdf

Also, ANY terrestrial planet around any star will probably lose the internal heat needed to keep plate techtonics going after 10 billion years or so. When that ends, the cycles that reprocess the geochemical needs of a biosphere will grind to a halt.

A lot of interesting studies going on ........................ what COROT and KEPLER may give us is a stat on
how prevalent the above fates are.

Craig

Posted by: nprev Aug 23 2007, 12:45 PM

So it seems that any true red dwarf exoEarths should blink rapidly enough for detection using mass sampling...sounds like a seed for a mission proposal, here, if the observable (key point; they're so damn faint that they'd have to be fairly nearby) number of dwarves is large enough to make it worthwhile.

Posted by: Greg Hullender Aug 23 2007, 03:53 PM

It seems that at least four factors help here: As you say, there are more red dwarves in the first place and more transits per unit of time. As JR pointed out above, there's a greater chance of having transits in the first place. There should also be a greater difference in brightness transiting a smaller star than a larger one.

One would predict that if Corot finds any "Earth-like" planets, they'll be around red dwarves, but if they find any, they'll find lots of them.

--Greg

Posted by: JRehling Aug 24 2007, 08:53 PM

Seems to me that possibility means two "habitable zones". One for the substellar point and one for the dark side.

Posted by: tty Aug 25 2007, 07:30 PM

That would depend on the amount of uranium present to begin with. Also geochemical cycling would not stop completely even in the absence of tectonics. For example glacial erosion can be very powerful and impact cratering would have some effect too. I would expect that some kind of low-nutrient, low-energy biosphere would persist rather like what we have in Australia (where there has been practically no tectonics over most of the continent for hundreds of million years).

Posted by: tacitus Aug 28 2007, 04:46 AM

While I understand that there are two target regions between which COROT will alternate every six months, I hadn't realized they were planning to observe new locations within those region each time the spacecraft came back to them. I can imagine that at some point (maybe in an extended mission) they might decide to return to a spot previously observed in an attempt to observe repeat events caused by planets with longer orbits.

I guess it all depends on what sort of data they observe in the first few observational runs. If they find a number of great Earth-sized candidates in one region, I should have thought they would be tempted to return to it the next year.

Posted by: PhilCo126 Aug 31 2007, 06:51 PM

In which parts of the Electromagnetic spectrum are COROT's detectors active ( Visible and radio for the astroseismology ? )

Posted by: Juramike Aug 31 2007, 08:05 PM

Not necessarily. A thick atmosphere could do a really good job of distributing heat. Both Venus and Titan (OK Venus isn't technically tidally locked - but you get the idea) have pretty much the same temperature on the nightside and dayside.

[And the "habitable zone" is really only a product of our surface prejudice for stable liquid surface water].

[And OK - Titan and Venus don't fit the description for fitting a "habitable zone" at the surface.]

IIRC, the paper belleraphon1 referenced took into account various greenhouse atmospheres expanding considerably our ideas of the "habitable zones" around M-class dwarfs. Atmosphere dynamics really matter, it's not just a bunch of hot air (sorry, couldn't resist).




As well as hot-spot volcanism. Without active plate tectonics to exchange heat the interior, I would imagine hotspots would develop to make up the exchange. Long-lasting calderas or hydrothermal systems might exist well into the "geochemical twilight".

Case in point: Io doesn't have plate tectonics but it does a pretty good job of staying active.

There may be local long-lasting habitation zones rather than a large overall habitable area. (Might make interesting isolated "biosphere islands" as well with lotsa cool possibilities for evolutionary divergence.)

I wouldn't discount any planets COROT finds as not being potential biospheres. (But I'd probably look more carefully at the cooler ones).

-Mike

Posted by: GravityWaves Sep 1 2007, 12:17 PM

I'd guess its 350nm-750nm range and it doesn't cover radio, basically the Europeans want to do highly sensitive measurements of a star from space that can't be done on the ground, hopefully NASA will be doing it soon with Kepler. Space is more stable, there is no heat/noise and the viewing time is uninterrupted. This is why a small telescope in the visible spectrum can outperform giant ground-based scopes. Corot will look at stars with an accuracy, stability, precision, and a duration off uninterrupted periods that are impossible to reach from our ground based telescopes.
I quote from the esa site
http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=31706
"The detectors are 4 CCD's 2048 x 2048 wide, (EEV, 13.5-μm thinned, back illuminated), working in the visible in the MPP mode. They are installed in the focal box, which is at a temperature of -40 °C with a variation that is less than 0.05 °C per hour.
For the seismology mission, the image spot for a star is spread out on about 400 pixels, with an exposure time of 1 second."

Posted by: ustrax Oct 2 2007, 10:53 AM

Malcolm Fridlund just told me that the number of exoplanets detected by COROT is...http://spaceurope.blogspot.com/2007/10/with-malcolm-fridlund-missions-project.html
The team started writing about ten new papers and a press event is predicted for the end of October, beggining of November.
What's coming from there?

Posted by: belleraphon1 Oct 2 2007, 01:31 PM

Thanks ustrax!!!!!

Can hardly wait.

A great paper recently published is:

MASS-RADIUS RELATIONSHIPS FOR SOLID EXOPLANETS
S. Seager, M. Kuchner, C. A. Hier-Majumder, B. Militzer4

http://fr.arxiv.org/PS_cache/arxiv/pdf/0707/0707.2895v1.pdf

On page 21 is a fantastic graph "Mass-radius relationship for solid planets" where the mass-radius lines for planets of different compositions are plotted.

Since the COROT team seems to be looking at ground-based confirmation of some of these detections, they must be looking for RV measurements to tie into the radii from the transits..... where on the "mass-radius relationship for solid planets" graph will these "planets" fall?

Craig

Posted by: ustrax Oct 3 2007, 08:50 AM

You're welcome and neither can I...
What will have this guys to present us?...
Thanks for the paper, it might get useful in the future!

Posted by: belleraphon1 Oct 3 2007, 12:18 PM

ustrax...

keep reporting....

I have the graph from the Seager et al paper hanging on my office wall. People drop in and see that and it gives me an excuse to launch into a discussion on extrasolar planets.

From the excellent site Extrasolar Planets Encyclopedia I get the following stats...
http://exoplanet.eu/catalog-all.php?&mode=2&more=

So far we have discovered the following population of planets that are less messive than Saturn (our smallest
gas giant in the Sol system)

Lower mass planets discovered aroung main sequence stars
31 planets < Saturn mass
12 planets < Neptune mass
4 planets < 10Eeath mass (super Earths?)

REALLY interested in what the COROT folks will present.

Craig

Posted by: nprev Oct 4 2007, 02:15 AM

Hoo boy...this could be a demarcation between one epoch & the next. Looking forward to your reports, US!!!

Posted by: brellis Oct 18 2007, 04:19 AM

Does anyone know when Epsilon Eridani b reaches its "Kodak Moment"? In October, 2006, a team from U Texas Austin http://www.astrobio.net/news/article2109

Is there a site listing transits of extrasolar planets?

Thanks,


Brad

Posted by: Del Palmer Oct 18 2007, 12:24 PM

Late December (the exact date depends on HST scheduling issues).

Posted by: ustrax Oct 18 2007, 04:22 PM

Got some words from Malcolm Fridlund telling that there will be a press release within the next few weeks.
Currently the team is debating how much to put in it.

...How much to put in?

...How much to put in?!

How about...everything??!!

Posted by: belleraphon1 Oct 18 2007, 06:58 PM

Agree... want EVERYTHING!!!

Thanks ustrax

Craig

p.s. you have a great blog....

Posted by: nprev Oct 19 2007, 03:52 AM

Agreed, Rui...overall excellence for your blog, you got me on the daily hook!

This is a cliffhanger...can hardly wait to see what they may tell us...

Posted by: ustrax Oct 19 2007, 08:10 AM

Thanks guys...

I woke up with this interrogation flying around my head...what to put in?...
Did he meant to say that, first...they are choosing the most important ones or...second...may it be a question of spectacular abundance of discovered exoplanets and they just can't decide what to present to the public?

Posted by: TheChemist Oct 19 2007, 11:53 AM

IMO they are debating where to draw the line that separates what they feel they can state with confidence, and the more speculative stuff.
If these two are clearly separated, it is no problem to announce both.
However, the press is always ready to jump on the vagon of speculation waving huge red flags, so the team's carefulness is understandable and appreciated.

Posted by: ustrax Oct 29 2007, 10:05 AM

The COROT announcement has been delayed...

Hold on! Before you start booing ESA this was done to permit the team to have their scientific publications written and submitted to refereed journals...
And there is already a date, Dec 10.

Posted by: belleraphon1 Nov 5 2007, 04:17 PM

All...

more hints from the COROT team.... "300 days in orbit"
http://exoplanet.eu/papers/CoRoT-300days.pdf

This was posted on the Extrasolar Planets Encyclopaedia site
http://exoplanet.eu/

Craig

Posted by: ustrax Nov 5 2007, 05:48 PM

Danke Craig!

Posted by: belleraphon1 Nov 5 2007, 07:41 PM

And thanks right back at cha!!!!!

I feel famous

Craig

Posted by: ustrax Nov 6 2007, 11:35 AM

You're welcome...

http://www.superwasp.org/wasp_planets.htm...this is getting boring...

Posted by: OWW Nov 6 2007, 08:01 PM

boring? never. BTW:

http://www.space.com/scienceastronomy/071106-five-planets.html

The party goes on.

Posted by: ustrax Nov 7 2007, 04:21 PM

You didn't take me seriously didn't you?...

Fridlund's teaser-update, a writing session, from where some papers should come out, will take place within two weeks, 20-21 Nov, in Paris...anyone around with sneaking abilities?

Posted by: belleraphon1 Nov 8 2007, 03:48 AM

My Mission Impossible days are over..... But Paris sure sounds nice to this USA midwesterner!!!!

I am, of course, hoping for big revelations, but seriously think that any report as big as terrestrial radii planets will probably have to wait for good solid RV mass determinatons... and this might be too soon for that.

At the least, they can report that planet transit probables are VERY common... which bodes well. Also believe there wil be a strong desire, given what they find, to trump KEPLER.

Noticed the audio press conference regarding 55Cancri f did not even mention COROT, but KEPLER was mentioned several times. I do not care WHO finds WHAT, as long as the exploration continues.

viva la planete!!!!!!

Craig

Posted by: ustrax Nov 8 2007, 12:05 PM

Debra Fischer visited the blog and her hopes, by what it seems to me, are not so on KEPLER but on JWST, and she mentioned COROT...
She also makes reference to her wish of seing a spaceborn astrometry mission but the costs man...the costs?!
Fischer hopes that resources can be pooled across the world, working together is the way she sees things happening...
That sounds good...EVERYONE finding EVERYTHING...

Posted by: belleraphon1 Nov 8 2007, 12:28 PM

Ustrax... just got back from your blog.

Nice interview with Debra Fischer.......

Cooperation is a necessity for the really large space telescope wish lists like SIM and TPF.

Found a white paper regarding JWST contribution of astrobiology (geez, I remember when we called it exobiology). http://www.stsci.edu/jwst/science/whitepapers/JWST-astrobio.pdf

There is a whole set of JWST white papers online
http://www.stsci.edu/jwst/science/whitepapers/

Given what Spitzer has contributed to exoplanet and dust disks research, JWST will be great!!!!!

Craig

Posted by: Rakhir Nov 10 2007, 07:19 AM

Sorry Ustrax but in addition to sneaking abilities I would also need splitting capacities because I will be in business trip in Italy at this time.

Posted by: brellis Dec 8 2007, 03:16 AM

brellis asked: "when will Epsilon Eridani b have its Kodak moment?"

DelPalmer answered:

Where might one find an HST observing schedule?
Will they be able to get a good look without ACS?

Posted by: brellis Dec 8 2007, 03:20 AM

found it

http://www.stsci.edu/hst/scheduling/weekly_timeline

Posted by: Phillip Dec 10 2007, 01:09 PM

Is December 10 still the day scheduled for the big COROT announcement? Any news?

Phillip

Posted by: Jyril Dec 11 2007, 01:03 PM

Apparently it wasn't.

And nope, nothing. The silence is deafening.

Posted by: Jyril Dec 11 2007, 04:41 PM

The COROT science team had a http://scienceblogs.com/catdynamics/2007/12/corot_update.php, but it was just a meeting, not an announcement.

The mission, like other transit searches, suffers from the fact that available telescope time is limited. The candidate planets must be confirmed using the RV method. In addition, it is very hard if not impossible to measure radial velocities caused by the smallest planets detected by the spacecraft.

Posted by: ustrax Dec 12 2007, 09:11 AM

This is being quite a rollercoaster not permitting much activity lately at spacEurope, but COROT deserves a special attention.
Just read an e-mail from Fridlund.
The press conference has been delayed, but not for long, where you have read the 10th http://spaceurope.blogspot.com/2007/12/long-time-no-see-hey-explaining-this.html...

Posted by: PhilCo126 Dec 12 2007, 10:52 AM

I'm preparing an article on COROT, looking forward to that briefing...

Posted by: belleraphon1 Dec 12 2007, 12:52 PM

Thanks Jyril and ustrax...

I think I am looking at the 20th as more of a COROT team progress update, rather than a formal "look at the planets we found"
announcement.

Any terrestrial sized planet candidates are going to take some sensitive RV verifications, and will take a lot of dedicated ground telescope time ..... so I am not expecting any thing along those lines.

Look forward all the same at learning how sensitive COROT is... the hints are tantalizing.

Craig

ps ustrax... good to see back with the blog!!!!

Posted by: NGC3314 Dec 12 2007, 02:35 PM

The most sensitive Doppler detections are possible for planets which are known to transit. The star's mean Doppler shift varies during transit as the planet covers up pieces rotating at different line-of-sight velocities (the Rossiter-McLaughlin effect, IIRC). The amplitude of this effect often exceeds the reflex Doppler signature of the planet on the star's motion, as shown from Doppler curves of known transiting massive planets, and if you have the transit ephemeris you can time your observations to be specifically during the transit rather than requiring multiple periods. So this is another way that transit candidates can help leverage spectroscopic capabilities in a powerful way. A good thing, too, since there are ways dim stellar companions can do a good job of mimicking the behavior of a planetary transit (notably grazing secondary eclipses).

Posted by: belleraphon1 Dec 12 2007, 05:24 PM

Good point NGC3314.

Ground based telescopes are doing some amazing things now.

They still have to get telescope time and wait for the target stars to be visible during the observing season. And before they announce terrestrial planets, they are going to want to really nail em down.

I do expect some really interesting announcements over the next few years....

Craig

Posted by: Phillip Dec 12 2007, 11:30 PM

December 20 = just in time for a nicely wrapped, little Christmas gift from Santa Corot, perhaps?

Phillip

Posted by: GravityWaves Dec 19 2007, 09:04 AM

The Chief Scientist, has been awarded a French medal - this sounds like he found something a lot more exciting than just another hot-jupiter. Press conference in Paris tomorrow, hopefully we will see some intriguing results then
will we be hearing anything from the astro seismology working group ?

Posted by: ustrax Dec 20 2007, 09:14 AM

Fridlund just informed from the time of the conference: 11AM, CET, with an article at ESA site at 1PM.

I'll try to get get something more soon...

Posted by: Jyril Dec 20 2007, 12:05 PM

http://exoplanet.eu/planet.php?p1=CoRoT-Exo-2&p2=b, a run of the mill transiting hot Jupiter. This can't be all they're revealing...

Posted by: ustrax Dec 20 2007, 12:11 PM

Information released http://www.esa.int/SPECIALS/COROT/SEMF0C2MDAF_0.html.

EDITED: Jyril...looks like that was it...

Posted by: belleraphon1 Dec 20 2007, 12:37 PM

From the press release:

"On 10 December 2007, the first set of data obtained by COROT was released to the Co-Investigators of the mission. These scientists hail from the member states of the COROT consortium (ESA, Austria, Belgium, Brazil, Germany, and Spain). The actual analysis of large amounts of data has just begun and is expected to speed-up with the release of the next data segment in February 2008.

In the data obtained, many light curves show signs of exoplanets in transit and are being followed-up from ground.
The discovery of COROT-exo-1b and COROT-exo-2b is described in three scientific papers that will be submitted to scientific journals in the next few days.

COROT has observed four regions so far:

One zone in the direction of the constellation of the Unicorn (Monoceros) for 60 days
Two regions in the opposite direction on the sky, towards the constellation of the Snake's tail (Serpens Cauda) – one short for 26 days and one long for 150 days.
A new region in the direction of the Unicorn, where COROT will remain for at least 150 days "


They mention the data has just been released - it does not surprise me that the first confirmed planets are hot jupiters.... those are "easy" to pull from the data.

We need patience..... I am sure there is much gold to be mined from the data.... it will just take time to identify candidates and them confirm with rv measurements.

We live in marvleous times....

Craig

Posted by: djellison Dec 20 2007, 12:41 PM

"COROT surprises a year after launch"

That's not surprising - that's what we expected.

DOug

Posted by: ustrax Dec 20 2007, 12:49 PM

full inline quote removed - did that surprise you - Doug

Yes...your reaction is no surprise either...that's what I expected too...

Posted by: djellison Dec 20 2007, 01:07 PM

I'm not playing down COROT...it's great - but saying that the discovery of X Jupiter mass planets is a surpise is about as surprising as the MER APXS finding a strong Fe signal on Mars. It's a great sign that everything's workign great, but going on what they hinted at at Europlanet - I was expecting a new type of discovery, not just a new discovery of a planet. 'On Course' - 'Performing Well' - those are appropriate phrases here. It'd be a surprise if it HADN'T detected planets like this.

Doug

Posted by: ustrax Dec 20 2007, 02:28 PM

OK...maybe surprise is not the right word...
I had somehow higher expectations regarding this...but...as said before and by others the best is on it's way...

The best of the release is, for me, the detection of oscillations in stars "very similar to our sun"...

EDITED: And what about this?...Isn't it exciting? 40 possible new exoplanets?!!
We're sooo spoiled...

"According to the COROT team there are already, and beyond the two exoplanets already discovered under the mission, CoRoT-exo-1b and CoRoT-exo-2b, around 40 light curves containing signs of possible planets.
Further ground analysis is necessary to confirm their true nature.

Among these possible exoplanets there are two candidates particularly promising...a planet two times smaller than Saturn and another one of jovian size but with a unusual density..."

Posted by: centsworth_II Dec 20 2007, 04:19 PM

Yes, that's it. Exciting, but not surprising. And I bet many people here
will not be surprised if many, many earth-sized planets are found when
the ability to detect them has been fully achieved. That will be immensely
exciting, but not in the least surprising.

Posted by: Jyril Dec 20 2007, 05:20 PM

Only 40? Based on other transiting surveys, most candidates turn out to be false positives so that is not much (yes, I'm spoiled...). On the other hand, they're only just started analyzing the data.

Posted by: climber Dec 20 2007, 06:59 PM

They said on the radio (France Inter) that they detected star vibrations. They put some sounds together but I cannot Google them properly. If somebody can.

Posted by: nprev Dec 20 2007, 07:14 PM

By star vibrations, do you mean astroseismological phenomena, Climber? If so, I suspect that's where the real "surprises" may be lurking in the data. Fine-scale periodic changes in a given stars pulsation patterns might provide clues about the existence of planets much smaller then 1 Mj, but it would be one hell of a job of analysis...

Posted by: tacitus Dec 21 2007, 12:32 AM

I was also looking forward to a big announcement. Ah well, that's the scientific process, I guess. It seems like it's going to take a good while to get the discovery pipeline cranking.

Posted by: ustrax Dec 21 2007, 10:23 AM

Only...but all of them are from Sun-like stars, that's...exciting...isn't it?
Even if not all are exoplanets, those being are really promising.

The jovian-sized candidate to which is made reference in the release by having an unusual density...got it...Fridlund finds it really odd, it has half the Saturn density, which indicates that this might be a planet with no metals at all...

Not wanting to advertise here just to say that Malcolm Fridlund made himself available to answer the questions of those reading spacEurope, if you guys have any thing you would like to see clarified from the press conference fo from the mission itself please, be my guest.

Posted by: JRehling Dec 21 2007, 06:01 PM

Not to be too big of a spoiler, but it's not clear that discovering more hot Jupiters really amounts to much useful science at all. We already know that a few percent of stars have them, and most of what's to do is to add some "N" to the statistics of number, size distribution, etc. I suppose a survey now could also help when the day comes that more sophisticated techniques exist to image them or perform spectroscopy. But in the short run, each new one discovered means very little.

We'll learn more by finding one terrestrial planet (or, improbably, prove the lack of existence thereof) than we would in finding 4 million more hot Jupiters or eccentric Jupiters. That's what makes this report so underwhelming. But of course, the mission is not done yet.

Posted by: climber Dec 21 2007, 06:23 PM

I'm not sure of what they said but they said it was unexpected that so many stars "vibrated"...and the sound was nice to ear actualy.

Posted by: centsworth_II Dec 22 2007, 05:43 PM

More important than just discovering their presence, I think, would be
determining orbit shapes and distances from host star.

Posted by: Jyril Dec 22 2007, 07:13 PM

It seems clear based on the transiting planets found so far that there is hot Jupiters are actually a very diverse group and new planets often offer surprises. For example, although CoRoT-Exo-2b seems a typical hot Jupiter, it is unusually massive for a "puffed-up" planet.

Posted by: edstrick Dec 23 2007, 10:22 AM

We will also be getting very "process-informative" statistics on the nature of hot jupiter and warm jupiter and hot neptune and warm neptune populations

We will use the statistics of the observed highly incomplete populations, back-projected as far as they can through "planet-detectability-filters", to create less incomplete estimates of planetary populations.

The resulting statistics will be increasingly informative as what the variations of star system properties (especially star mass and metalicity) have to do with resulting planetary system formation and evolution.

Posted by: dvandorn Dec 23 2007, 05:36 PM

It's also possible that extensive study of these hot gas giant systems could disclose that every solar system, sooner or later, finds its gas giants migrating in to close orbits and eventually impacting into their stars. Such information would be useful to us, don't you think?

-the other Doug

Posted by: JRehling Dec 23 2007, 09:19 PM

Since the process by which migration would happen requires lots of debris for the giants to collide with, I think we can call the process over in our solar system. Even if every remaining comet hit Jupiter, it wouldn't make much difference in its orbit.

Posted by: edstrick Dec 24 2007, 06:22 AM

It's a ***HIGHLY*** biassed sample, and though the better the statistics get, the better we can "un-bias" it...there's a real limit how far you can go. There may be highly regular solar systems with no gas giants or only Neptune mass objects in orbits beyond a few AU, and we'd have utterly no clue they exist so far, etc, etc. There may be systems that just never formed planets, but have debris belts that have thinned down over time so they're no more obvious than our asteroid or Kuiper belts.

One big "Uh.. I don't hear discussion of this" things (but since I'm not digging into the research papers I may have missed it) is a question of a system's rotational angular momentum to stellar mass ratio. If you have a strongly rotating pre-stellar cloud, it may form a solar mass star with a massive disk. If you have a weakly rotating one of slightly lower mass, it might form an essentially identical star, but with much less mass in the nebula. This would be totally independent of the metallicity that does appear to be important. There may be essentially no main-sequence indication from a star's spectrum of the nebula's initial angular momentum... but it could result in dramatically different types of planetary systems, statistically.

Has anybody heard discussion on this?

Posted by: dvandorn Dec 24 2007, 07:28 AM

Well -- yes, but. The migration process doesn't require tons of big debris chunks. A long enough transit through gas clouds dense enough to collapse the heliopause inside the orbit of Jupiter could set it going again, I bet. The upcoming collision (in something more than 2 billion years) between the Milky Way and M31 might provide the right conditions for outer planet migration to begin again, after all. And there's some good theories out there that the Magellanic Clouds are remnants of a galactic collision that occurred since our own Solar System formed -- they could have provided a lot of gas and dust clouds through which a lot of systems might have plowed.

Also -- from my best understanding, all these hot Jupiters, if they are indeed gas giants, had to have formed a lot farther from their suns than where they are at present, right? My best understanding of current planet formation theory is that gas giants won't form until it's cold enough for ices to maintain themselves without solar radiation boiling them off into vapor. So, these hot Jupiters must have migrated all the way in to where they are, right? And they're pretty darned abundant, right?

So... seems to me it might be a good idea to start understanding exactly what conditions can cause migrations to start and stop. Just to be on the safe side.

-the other Doug

Posted by: nprev Dec 24 2007, 04:22 PM

On the subject of system angular momentums, has anybody derived stellar rotational periods for all these systems? Curious to see what sort of correlations may have been observed; hot Jupiters have to be placing some significant drag on their parent stars.

Posted by: Jyril Dec 24 2007, 06:16 PM

The outer layers of Tau Boötis http://www.space.com/scienceastronomy/050523_star_tide.html with its planet.

Posted by: nprev Dec 24 2007, 06:42 PM

Thanks, Jyril; most informative!

So, this begs a question or two. Given that the Sun's photosphere has something like a 28-day rotation period, should we be looking at stellar rotation periods in order to find systems with terrestrial planets, with the postulate that stars close to this period might have a solar system analogous to our own? Too fast al a Tau Bootis means a hot Jupiter, which presumably migrated inward & disrupted the inner planets; likewise, intermediate fast (I don't know; say <14 days?) might mean that, absent of any observed 'wobbles', there isn't much mass in the system outside of the star itself.

The variety of systems observed to date certainly means that this approach alone is too deterministic, and ignores many other important factors. Still, the parameter of stellar rotational rate may well be an important discriminator in the future for finding the precise types of planets we want to study when we have to sift through TBs of data.

Posted by: Greg Hullender Dec 24 2007, 10:33 PM

nprev: I remember reading Poul Anderson's "Is There Life On Other Worlds" as a kid in the late 1960s, in which he postulated that stars with high angular momentum didn't have planets, and he was encouraged by the fact that most sunlike stars do indeed rotate more slowly. Today, doing a few web searches, it appears that the moden consensus is that all stars gradually lose angular momentum through interaction with their solar winds, and that sunlike stars tend to rotate more slowly simply because they tend to be older. No connection with planets, unfortunately.

In the process, though, I ran across the following interesting paper:

http://arxiv.org/abs/0708.1771

"Angular momentum in our solar system is largely distributed between the Sun's rotation and the planetary orbits, with most of it residing in the orbital angular momentum of Jupiter. By treating the solar system as a two body central potential between the Sun and Jupiter, one can show that the orbital specific angular momentum of the two-body system exceeds the solar rotational specific angular momentum by nearly two orders of magnitude. We extend this analysis to the known extrasolar planets available in the Extrasolar Planet Encyclopedia and estimate the partitioning of each system's angular momentum into orbital and rotational components, ignoring the spin angular momentum of the planets. We find the range of partitioning of specific angular momentum in these systems to be large, with some systems near the stellar rotational limit, and others with orbital specific angular momentum exceeding this limit by three orders of magnitude. Planets in systems with high specific angular momentum have masses greater than two Jupiter masses, while those in systems with low specific angular momentum are below two Jupiter masses. This leads to the conclusion that low mass planets lose angular momentum more efficiently, and are thus more prone to migration, than larger mass planets. "

--Greg

Posted by: Jyril Dec 27 2007, 02:57 PM

From http://spaceurope.blogspot.com/2007/12/we-are-on-day-after-corot-press.html:

Never heard of http://exoplanet.eu/star.php?st=TrES-4? It is the largest planet known, R = 1.674 R_J, but less massive than Jupiter (M = 0.84 M_J). Its density is only ρ = 0.22 g/cm³. In fact, 0.35 g/cm³ is not at all unusual for a puffed up hot Jupiter. For example, the prototype transiting planet, HD 209458 b, has a density of 0.37 g/cm³. I don't understand the hype.

It would be more unusual, if the planet was much more massive than Jupiter. But on the other hand, we know such a planet, namely CoRoT-Exo-2b which is unusually massive for a puffed up planet.

Posted by: PhilCo126 Dec 30 2007, 12:04 PM

In fact, COROT exists of two major parts:
The spacecraft bus PROTEUS (Plate-forme Reconfigurable pour l'Observation, pour les Télécommunications et les Usages Scientifiques) on which sits:
The scientific payload consisting of 27-cm telescope, wide field camera and equipments bay with electronics…
Does anybody know where to get high-resolution photos of the spacecraft integration (Alenia Space ?)

Posted by: PhilCo126 Dec 30 2007, 12:20 PM

e.g. http://www.saftbatteries.com/000-corporate/pdf/CP67-06_COROT_copyright__studio_bazile2006.jpg

Posted by: nprev Jan 3 2008, 03:51 PM

http://www.spaceurope.blogspot.com/ has been updated with Q&As for mission scientist Malcom Fridland...go, Rui!

Posted by: Mongo Jan 3 2008, 06:49 PM

The most interesting answer (in my opinion):

Q: How you will deal with single transit planets? If Corot clearly spot the transit of a planet only one time, will this planet followed by the ground? Its orbital period could be obtained only by the duration of the transit? I read for example that the Kepler mission will be able to confirm a jovian planet after only seeing a transit. I wonder if Corot will be able to do the same...

A: We are already doing that. We have transits that occur only once (and of 2 or three transits during the 150 days but there will be more). Clearly this will be very difficult for small planets.

Posted by: ustrax Jan 4 2008, 09:27 AM

I'm expecting your questions...

A comment at http://oklo.org/?p=262#comments might lead to hink that there I will select questions, erasing the inconvinient ones...:
"“I guess now you can ask yourself your own incovenient questions to COROT team”
Yes, but guess who selects questions? This is through spaceurope@gmail.com…"

That is complete nonsense, every question arriving the mailbox will be adressed to Dr. Fridlund, or God, as someone might see it...

Posted by: nprev Jan 4 2008, 04:49 PM

Okay, I got one. Dr. Fridland states that COROT can see starspots (and I'm assuming that this is done by detecting very small variations in the light curves of the stars). Is this data being used to derive the percentage of a given star's surface that's spotted? Seems like valuable astrophysical data worth acquiring & analyzing.

Posted by: PhilCo126 Jan 4 2008, 05:30 PM

How you will deal with single transit planets?
Indeed an interesting question which will re-schedule the already very busy schedules of ground-based telescopes. Anyway, let's hope that the search for exo-planets will give an extra stimulation of the budgets for the planned 'monster telescopes' in Chile (European Extremely Large Telescope: EELT with 42 meter mirror / US Giant Magellan Telescope with 24.5 meter mirror)

Posted by: ustrax Jan 4 2008, 05:51 PM

Is that a question for Malcolm Fridlund?
If you guys want to throw in some more untill the 7th I can gather these and present to MF and at the blog as UMSF's joined efforts to generate the most important questions in order to obtain the most valuable answers...

I know you guys can leave him breathless...

Posted by: nprev Jan 4 2008, 06:08 PM

Rui, JR's earlier comment just stimulated another question, but it may be beyond the scope of the topic. Based on the COROT observations to date in addition to ground-based discoveries, do we see any correlation at all between estimated system ages & the dynamical state of planetary systems? What I mean is do we see systems older than ours with hot Jupiters/Neptunes, or younger, or is there no discernable relationship?

Posted by: hendric Jan 4 2008, 09:42 PM

I think a single event light curve could give scientists enough information to predict, roughly, the orbit of the planet in question, and estimate when the star should be observed for the next transit.

The size of the star can be estimated based on its type. If the transit shows a flat bottom that proves the transit was complete, not partial. The amount of dimming gives the relative diameter of the planet. The slope of the entry/exit curves shows at what latitude the transit occured. Once you know all these, the orbital speed can be determined. Once you have that, the only big unknown would be eccentricity.

Then again, maybe the error bars on any such calculation would be make it pretty much useless.

Posted by: Mongo Jan 4 2008, 09:57 PM

Actually, that question was already answered -- see my post from yesterday.


Don't forget the US/Canadian TMT (Thirty-Metre Telescope) with over 200 million dollars already donated or pledged, which will probably be built on a Chilean mountain-top -- three of the five sites under consideration are in Chile. Plus the US 8-metre LSST (Large Synoptic Survey Telescope) currently under construction on Cerro Pachon. Add these to the already operational 8-metre class telecopes (VLT @ 4x8.2 metres; Gemini South @ 8.1 metres; Walter Baade (Magellan I) @ 6.5 metres; Landon Clay (Magellan II) @ 6.5 metres) and you have an incredible collection of ground-based telescopes.

There is also the planned US/UK/Canadian 25-metre CAT (Cornell Atacama Telescope) in the IR.

Posted by: ustrax Jan 4 2008, 10:51 PM

Yes I know Mongo that is why I was asking...

I wasn't aware of the majority of the telescopes you have made reference too...golden age just ahead...
Where will will be 20 years from now?
With COROT data, with Kepler, with all the toys on the way...man! We'll see alien's underware!

Any additional questions?...
The 7th is the limit.

Posted by: Mongo Mar 24 2008, 12:33 PM

First CoRoT results:

http://xxx.lanl.gov/abs/0803.3202

Context. The pioneer space mission for photometric planet searches, CoRoT, steadily monitors about 12,000 stars in each of its fields of view; it is able to detect transit candidates early in the processing of the data and before the end of a run.
Aims. We report the detection of the first planet discovered by CoRoT and characterizing it with the help of follow-up observations.
Methods. Raw data were filtered from outliers and residuals at the orbital period of the satellite. The orbital parameters and the radius of the planet were estimated by best fitting the phase folded light curve with 34 successive transits. Doppler measurements with the SOPHIE spectrograph permitted us to secure the detection and to estimate the planet mass.
Results. The accuracy of the data is very high with a dispersion in the 2.17 min binned phase-folded light curve that does not exceed 3.10-4 in flux unit. The planet orbits a mildly metal-poor G0V star of magnitude V=13.6 in 1.5 days. The estimated mass and radius of the star are 0.95+-0.15Msun and 1.11+-0.05Rsun. We find the planet has a radius of 1.49+-0.08Rjup, a mass of 1.03+-0.12Mjup, and a particularly low mean density of 0.38 +-0.05g cm-3.

http://xxx.lanl.gov/abs/0803.3207

Context. The CoRoT mission, a pioneer in exoplanet searches from space, has completed its first 150 days of continuous observations of ~12000 stars in the galactic plane. An analysis of the raw data identifies the most promising candidates and triggers the ground-based follow-up.
Aims. We report on the discovery of the transiting planet CoRoT-Exo-2b, with a period of 1.743 days, and characterize its main parameters.
Methods. We filter the CoRoT raw light curve of cosmic impacts, orbital residuals, and low frequency signals from the star. The folded light curve of 78 transits is fitted to a model to obtain the main parameters. Radial velocity data obtained with the SOPHIE, CORALIE and HARPS spectro-graphs are combined to characterize the system. The 2.5 min binned phase-folded light curve is affected by the effect of sucessive occultations of stellar active regions by the planet, and the dispersion in the out of transit part reaches a level of 1.09x10-4 in flux units.
Results. We derive a radius for the planet of 1.465+-0.029 R_Jup and a mass of 3.31+-0.16 M_Jup, corresponding to a density of 1.31+-0.04 g/cm^3. The large radius of CoRoT-Exo-2b cannot be explained by current models of evolution of irradiated planets.

http://xxx.lanl.gov/abs/0803.3209

We report on the spectroscopic transit of the massive hot-Jupiter CoRoT-Exo-2b observed with the high-precision spectrographs SOPHIE and HARPS. By modeling the radial velocity anomaly occurring during the transit due to the Rossiter-McLaughlin (RM) effect, we determine the sky-projected angle between the stellar spin and the planetary orbital axis to be close to zero lambda=7.2+-4.5 deg, and we secure the planetary nature of CoRoT-Exo-2b. We discuss the influence of the stellar activity on the RM modeling. Spectral analysis of the parent star from HARPS spectra are presented.

Posted by: GravityWaves Jul 25 2008, 02:39 AM

COROT’s new find orbits Sun-like star

http://www.esa.int/esaCP/SEMSIFXIPIF_index_0.html

Posted by: Mongo Jul 25 2008, 03:50 PM

*sigh*

http://www.aanda.org/index.php?option=article&access=standard&Itemid=129&url=/articles/aa/abs/2007/47/aa8787-07/aa8787-07.html

Another ESA 'first' that really isn't?

Posted by: dvandorn Jul 25 2008, 04:30 PM

And if ESA keeps claiming "firsts" that aren't, doesn't that constitute prevarication?

Sorry -- I guess I'm a little sensitive, yet, for being yelled at by a member of this forum for characterizing ESA's PR as including "little lies." But, but, but -- if these aren't self-aggrandizing lies, what in the Cosmos are they?

-the other Doug

Posted by: Del Palmer Jul 25 2008, 04:50 PM

I'd say it was badly worded. It is, after all, the longest period for any transiting exoplanet ever found via the transit technique. There are other transits with longer periods (such as the one you reference) but all of those were first found by radial velocity searches, and then analyzed for transit solutions.

Posted by: djellison Jul 25 2008, 04:56 PM

No - it's not a case of wording it badly - it's just wrong. Not even a hint of acknowledging the other work in the field. This, after the 'bad wording' of claiming that MEX would be seeing unseen parts of Phobos (when actually it's parts of Phobos already seen...just not by MEX) wraps up a bad week for ESA imho.

Bad form.

Posted by: dilo Jul 25 2008, 08:58 PM

It is not clear how they measured star rotation period, even if, by reading article, it seems that they monitored solar spots on its surface. A silly question at this point is: could be the planet a huge great spot?
I guess that doppler measures from Earth support it's planetary nature...

Posted by: climber Jul 25 2008, 09:24 PM

Or a spider on the optic : http://en.wikipedia.org/wiki/The_Shooting_Star

Posted by: JRehling Jul 25 2008, 09:48 PM

If it were, it would foreshorten at the limb and only be at its full apparent size when it crosses the central meridian. A transiting planet would be exactly the same apparent size as soon as it crossed fully in front of the star's disk and would stay precisely that size until it began to exit transit. So the light curve should answer this unambiguously unless the signal-to-noise ratio is very poor.

Posted by: dilo Jul 25 2008, 10:05 PM

Good observation, JRehling.
Anyway, I found two preprint articles (http://fr.arxiv.org/abs/0807.3767,http://fr.arxiv.org/abs/0807.3739) confirming that planet period is supported by Doppler observations and that star rotation was derived from tiny light curve modulations on short intervals (2/3 rotations). Interestingly, the two period aren't exactly coincident (9.20205 +/- 0.00037 and 8.87 +/- 1.12 days respectively) and sincronicity could be not exact but only close coincidence.

Posted by: mps Jul 26 2008, 12:22 PM

Actually, it's old news, from 19 May
http://exoplanet.eu/newsArchive.php

Really, doesn't the ESA press office have nothing better to do...

Posted by: PhilCo126 Jul 26 2008, 04:24 PM

As this is the holiday period, I guess they're trying to get the item in the " daily news "

Posted by: Hungry4info Jul 26 2008, 04:24 PM

Here, look at the light curve for CoRoT-Exo-4. As a star rotates, any sunspots will be carried in and out of our view by the rotation of the star. This shows up as small dips in the brightness of the star. These dips are readily apparent in the light curve of CoRoT-Exo-4, and furthermore, occur at regular intervals and with the same periodicity as the transits (visible as deep gashes "teeth" in the light curve). The dips in brightness caused by the sunspot I have marked with a red arrow.



It is also quite easily to distinguish between the planet transit and the sunspot. The dips in brightness caused by the spot are variable, just like the spots themselves.

Posted by: Mongo Jul 26 2008, 04:45 PM

Just to add to the above, a starspot would be visible for about half of the stellar rotation period, while a transiting planet would be visible for only a few hours per orbit. As the above image shows, the dip due to the transit is much shorter in duration than the dip due to the starspot.

Posted by: Juramike Jul 26 2008, 04:45 PM

That's kinda weird, isn't it? Any chance the planet is raising tides on it's star and affecting sunspot location?

-Mike

[EDIT: I meant magnetic effects, like Io's effect on Jupiter's magnetic field.]

Posted by: Hungry4info Jul 26 2008, 05:05 PM

I think this is what we find at Tau Bootis. CoRoT-Exo-4b has a 9.2-day orbit, a bit farther out from Tau Bootis b to it's star. I don't know how much the distance affects the possibility of that. I guess it could be possible. I don't know for sure.

Posted by: Del Palmer Jul 27 2008, 04:02 PM

The planet could well be inside the Alfven radius (the region where Alfven waves would transport large amounts of energy along field lines). Star-planet magnetic interaction would be seen as chromospheric enhancement, and such has been observed for HD 179949. COROT could answer this question itself by following-up the discovery with chromospheric observations.

Posted by: Del Palmer Jul 27 2008, 04:20 PM

Although tau Bootes is a likely candidate for magnetic interaction, it doesn't appear to be obvious in observations. It is suspected that the low relative velocity between the star and planet would not induce an appreciable current.

Posted by: Rakhir Sep 7 2008, 03:37 PM

1st international symposium dedicated to the scientific results of CoRoT, february 2-5, 2009 in Paris
http://www.symposiumcorot2009.fr/

Posted by: PhilCo126 Oct 23 2008, 06:34 PM

COROT sees Sun-quakes in other stars: http://www.esa.int/SPECIALS/COROT/SEM6D4RTKMF_0.html

Posted by: stevesliva Oct 23 2008, 08:22 PM

Guess I have to wait for the article to be up an nature to read what the results of the long-planned observations are.

Posted by: Tom Womack Oct 25 2008, 06:19 PM

There's some reasonably interesting information to be gleaned from the presentations at the workshop on COROT a few weeks back at the Paris Observatory; start at http://ecole-doctorale.obspm.fr/rubrique200.html and get repeatedly annoyed by the interface they're using for storing presentations. Do so quite soon since they're taking the presentations down at the end of October.

It's mostly grad-student-level material on asteroseismology and spacecraft design, but there's more information about the data-processing issues with COROT than I've seen elsewhere, and a few more light curves.

Posted by: stevesliva Oct 27 2008, 09:30 PM

The Science article is up, but I can't take a look-- not that I'd glean that much from it. I was just a little put off by the press release's declaration of observations, but no real findings. In unlocked websites, I find this little blurb:

Posted by: ustrax Feb 3 2009, 03:20 PM

YES! Quite surprising isn't it?
http://www.esa.int/SPECIALS/COROT/SEM7G6XPXPF_0.html

Posted by: Andrei Feb 4 2009, 11:12 AM

Wow! That's a fast planet!
My back of the datasheet...ahem...envelope.... calculation gave me a distance form the central star around 17.3 e-3 of the Earth mean orbital radius assuming the central star being identical with the Sun and a circular orbit. That gives around 2.59 millions km from the central star, or only about 3.7 Sun radii! That sure is close to the star. And the mean orbital velocity is around 225km/s!
Using the given diameter in the press release my calculations are telling me that Corot detected a drop in the star's light of only 0.02-0.03% for about 1 and 3/4 hours. That's quite a performance from the Corot team and I wonder how did they extracted this information form the noise in the light curves (from the graph posted above by Hungry4info for CoRoT-Exo-4 I see they have around 0.4% of the star light peak-to-peak noise - well, in the sub-percent range but much higher than 0.02-0.03%). Are they using some sort of autocorrelation on light curves to isolate the repetitive signals (i.e. repeated transits) out of the noise? But in this case how do they infer the duration of the transit? (i.e. based on the harmonic's number and peak value?). Does anybody have some insights into that?

EDIT - typed an extra zero!

Posted by: Tom Womack Mar 9 2009, 11:53 PM

I notice that the raw data is now available at http://idc-corotn2-public.ias.u-psud.fr/invoquerSva.do?sva=browseGraph at least for the first two sessions of COROT observations.

I collected the monochromatic data for the initial session, which is 5600 data series each of about ten thousand points; easy to parse, and my initial analysis was to find ones where the standard deviation of the measurements divided by the average of the measurement standard deviations was large, and then to look at (99th percentile brightness - 1st percentile brightness) / (1st percentile brightness): that gives the gallery at http://fivemack.livejournal.com/182633.html#cutid1

The pretty curves are mostly eclipsing binaries; could someone give me an idea of what the geometry implied by a light curve like http://www.chiark.greenend.org.uk/~twomack/corot/C0102791304.png is? I can get periods to four decimal places by trying to minimise the sum of the standard deviations of the amplitudes in 64 buckets collected under the purported period, but I don't see how to get to the six decimal places that astronomers often seem to mention for orbital periods.

I assume that cataclysmic variables are much less common than cosmic-ray hits on the CCD, but I don't have a very clear idea how to go about cleaning up the sudden jumps that you see in time series like http://www.chiark.greenend.org.uk/~twomack/corot/C0102741414.png - I don't think that 30% jumps in flux in less than one 512-second sample period are likely to be of astronomical origin.

Posted by: Hungry4info Mar 10 2009, 01:34 AM

Looks like a very tight (contact?) binary, with the secondary star being much smaller and dimmer than the primary. The primary star seems to be severely warped, and as it rotates, seeing it along it's widest axis, and then by its shortest axis, would seem to dominate the influence of the light curve. The quick teeth transits are probably the small secondary star transiting across it. As no secondary eclipse is apparent, the secondary, small star must be quite, quite dim.

That's just my guess.

Posted by: siravan Mar 10 2009, 03:13 AM

I concur. I guess it is a W Ursae Majoris variable (http://en.wikipedia.org/wiki/W_Ursae_Majoris_variable). Also, see the link below for a sample light curve:

http://members.dslextreme.com/users/rstephens/PDFFiles/GSC_1839-78_Paper.pdf

Posted by: Tom Womack Mar 10 2009, 08:51 AM

That's a nice paper, but I don't believe this is a W UMa, because they tend to have periods around ten hours and this one has a period of fourteen days. There are lots of W UMa stars in the gallery, visible by the thickness of the band at the small size of the thumbnails; http://www.chiark.greenend.org.uk/~twomack/corot/C0102806220.png (period ~.349692 days, phased light curve http://www.chiark.greenend.org.uk/~twomack/corot/806220-phased-.349692 ) looks a classic example.

I'm thinking it's a beta Lyrae with components of very different brightness, which I suppose is the same as an Algol with an elliptical primary; period looks about 13.58 days and when you phase on that the secondary eclipse becomes visible. Data (time/flux pairs) attached if anyone happens to have a binary-star-modelling program; when I think of modelling rotating ellipsoids from scratch, my head fills with ℘ symbols, and I hope somebody else has already written the software even before I think about limb-darkening.

Posted by: ustrax Mar 30 2009, 05:21 PM

Bad news...CoRoT has lost one if its detector chains, the same as saying that its field of view has been cut to half.

Posted by: Hungry4info Mar 30 2009, 10:18 PM

CRAP.
That really hurts to know. But thanks for that update.
Do you have a link to something official on it?

Edit:
http://beyondthecradle.wordpress.com/2009/03/30/corot-update-with-malcolm-fridlund/#more-373

Posted by: ustrax Mar 31 2009, 08:31 AM

Nope...been looking for it myself but even on the mission's website CoRoT is as it should be...well...
http://smsc.cnes.fr/COROT/

Guess we'll have to trust Malcolm's words...
Let's look to it on the positive side, they're refining the look over the already acquired data...let's see what surprises may be hidden there...

Posted by: PhilCo126 Mar 31 2009, 04:10 PM

Well COROT did detect the smallest exoplanet so far; COROT-Exo-7b in constellation Monoceros (Unicorn) at 400 Light Years.
Let's hope they can finish the mission...

Posted by: ustrax Apr 9 2009, 11:57 AM

Looks that will be no problem, according to Fridlund they're getting, with one detector, more and better data than before...
More details on the detector issue:
"The data chain 1 is gone for the moment. We do not want to heat up the spare data link onboard (where we think the error is) at this time because one need to turn everything off first."
You can read the rest at http://beyondthecradle.wordpress.com/2009/04/09/corot-update-more-and-better-data-with-malcolm-fridlund/.

EDITED: Sorry if my interpretation of english fails me here but aren't these words a great proof of humilty by the mission's PS?
I am certain that the dearth of Neptunes in our data is because of our search algorithms. I think the external access to our data is going to be a huge improvement."

Posted by: Greg Hullender Apr 9 2009, 04:45 PM

I agree, and it's great he's doing it. Pattern Recognition is such a huge area these days that it's no longer possible to be an expert in all of it, so I think there's no shame is his admitting that his team's search algorithms are probably missing lots of things.

--Greg

Posted by: ustrax May 18 2009, 10:18 PM

CoRoT-Exo-7b definitely Rocky!
"1.6 earth radii and 5.8 earth masses is 5.7g cm-3 and mars is only 4"
Facebook update with Malcolm Fridlund at BtC.
http://beyondthecradle.wordpress.com/2009/05/18/rocky-corot-exo-7b-update-with-malcolm-fridlund-via-facebook/

Posted by: Juramike May 27 2009, 09:44 PM

space.com article about CoRoT detecting phases of hot Jupiter exoplanet CoRoT-1b:

http://www.space.com/scienceastronomy/090527-exoplanet-phases.html

Oddly, CoRoT-1b doesn't have a lot of heat transfer between the dayside to the nightside.

Posted by: belleraphon1 Jun 5 2009, 01:47 AM

Corot's Littlest Exoplanet.... CoRot-7b and system
from Missions for Exoplanets: 2010-2020, Pasadena, April 2009
see Corot Update in Exoplanet Encyclopedia Bibliography for June 4th,2009
http://exoplanet.eu/biblio.php

system of three planets... one Super Earth, other two Hot Neptunes..

http://exep.jpl.nasa.gov/presentations/48-03-2-Fridland.pdf

Craig

Posted by: Hungry4info Jun 5 2009, 04:11 PM

Yeah, we had that posted on the http://solar-flux.forumandco.com a few months back, and someone apparently involved with the project informed us that the information within is not for public disclosure yet. He asked us to remove it, and we complied.

I do not know if it is still embargoed or not.

Posted by: belleraphon1 Jun 6 2009, 04:10 PM

Interesting Hungry4info

I check the Exoplanet Encyclopedia Bibliography daily. Very rich source of exoplanet information. Since the link to this presentation just showed up there perhaps we are past embargo? Exoplanet Encyclopedia is also a public site.

?????

Craig

Posted by: belleraphon1 Jun 8 2009, 12:04 AM

AHHHH....know how tired I was last Friday... it is the The Extrasolar Planets Encyclopaedia, NOT exoplanet.
A great resource.

Extrasolar planet forum... was not aware that existed. Thanks for the link.

Craig

Posted by: PhilCo126 Jul 29 2009, 06:00 PM

At the Observatoire de Haute Provence in France, I got the opportunity to follow a team of Franco-Swiss astronomers who're double checking candidate exo-planets detected by CoRoT (between 30 - 40 every 6 months) by using the SOPHIE spectrograph of the 1m93 telescope.
They're very busy but there will be a quiet period as the mirror needs to be recoated at the end of August, which will be reflected in "delayed" sharing of results...

Posted by: Mongo Jul 31 2009, 02:14 AM

http://xxx.lanl.gov/abs/0907.5150

Context: CoRoT is a pioneering space mission devoted to the analysis of stellar variability and the photometric detection of extrasolar planets.

Aims: We present the list of planetary transit candidates detected in the first field observed by CoRoT, IRa01, the initial run toward the Galactic anticenter, which lasted for 60 days.

Methods: We analysed 3898 sources in the coloured bands and 5974 in the monochromatic band. Instrumental noise and stellar variability were taken into account using detrending tools before applying various transit search algorithms.

Results: Fifty sources were classified as planetary transit candidates and the most reliable 40 detections were declared targets for follow-up ground-based observations. Two of these targets have so far been confirmed as planets, COROT-1b and COROT-4b, for which a complete characterization and specific studies were performed.

Posted by: belleraphon1 Jul 31 2009, 08:29 PM

Paper on COROT-7b now available.

Transiting exoplanets from the CoRoT space mission VIII. CoRoT-7b: the first Super-Earth with measured radius

http://exoplanet.eu/papers/corot-7b_phot_v37.pdf

Craig

Posted by: belleraphon1 Jul 31 2009, 08:33 PM

From research paper Mongo noted above - Planetary transit candidates in COROT-IRa01 field
http://fr.arxiv.org/PS_cache/arxiv/pdf/0907/0907.5150v1.pdf

"They use the CoRoTlux transit survey simulator described
in Fressin et al. (2007) to show that the CoRoT yield on
the first 4 fields is less than one-half that expected. This gap
will probably be reduced as the follow-up of CoRoT candidates
nears completion. Fressin et al. (2007) provides an estimate of
the planet occurrence in close orbit around F-G-K dwarf stars
as a function of the radius of the planet, which agrees with
radial velocity, ground-based transit, and CoRoT discoveries.
Interestingly, they show that CoRoT’s detection of one Super-
Earth (i.e., CoRoT-7b submitted by L´eger et al. 2009) agrees
with the high expectations fromthe HARPS team for the number
of close-in Super-Earths (i.e., for 30 % of main-sequence dwarfs
- see Lovis et al. (2009)), because this kind of planets typically
needs to have a bright K dwarf host to exceed the CoRoT detection
threshold."

Craig

Posted by: PhilCo126 Aug 1 2009, 11:51 AM

CoRoT's initial mission duration was 30 months but it looks like the mission was extended to January 2010.
How was this accomplished, less usage of cryo liquid?

Posted by: PhilCo126 Aug 4 2009, 11:44 AM

The CoRoT mission had a built-in possibility for extension, and the launch vehicle put the telescope in a very good orbit (errors +90m - 200m deviation from circular at 900km altitude) so they didn't burn ANY fuel for orbit maintenance so far.
Due to the loss of 50% detector array, the telescope observes shorter times now (90 days instead of 150 days) in order to cover
the same amount of stars. Wishing them best of luck...

Posted by: belleraphon1 Sep 16 2009, 10:57 AM

Announcement of Corot-7c in scientific literature.

"From this work we present independent evidence establishing the planetary nature of CoRoT-7b transit detection. The mass of CoRoT-7b is measured within a 20% accuracy. From the radial velocity data we show the presence of another planet, CoRoT-7c . If one assumes that both planets are on coplanar orbits CoRoT-7c (the second planet) belongs also to the category of Super-earth planets."

http://exoplanet.eu/papers/corot7-RV.pdf

Enjoy...

Craig

Posted by: PhilCo126 Sep 19 2009, 04:43 PM

They didn't bother to put the constellation in the text, but CoRoT-7b orbits a star in the constellation Monoceros (Unicorn).
The spacecraft views Unicorn in the winter and the constellation Snake in the summer...

Posted by: Byran Sep 22 2009, 11:16 AM

COROT 1000 days in orbit!
http://smsc.cnes.fr/COROT/

Posted by: Paolo Oct 23 2009, 05:39 AM

An issue of Astronomy & Astrophysics entirely dedicated to Corot (and accessible for free!)
http://www.aanda.org/articles/aa/abs/2009/40/contents/contents.html

Posted by: Paolo Dec 27 2009, 09:06 AM

http://arxiv.org/abs/0912.4655

Posted by: Greg Hullender Dec 27 2009, 04:15 PM

Actually it's a very nice summary of the CoRot results to date, and the PDF is even free. Here's the abstract:

The up to 150 day uninterrupted high-precision photometry of about 100000 stars – provided so far
by the exoplanet channel of the CoRoT space telescope – gave a new perspective on the planet population of
our galactic neighbourhood. The seven planets with very accurate parameters widen the range of known planet
properties in almost any respect. Giant planets have been detected at low metallicity, rapidly rotating and active,
spotted stars. CoRoT-3 populated the brown dwarf desert and closed the gap of measured physical properties
between standard giant planets and very low mass stars. CoRoT extended the known range of planet masses
down-to 5 Earth masses and up to 21 Jupiter masses, the radii to less than 2 Earth radii and up to the most
inflated hot Jupiter found so far, and the periods of planets discovered by transits to 9 days. Two CoRoT planets
have host stars with the lowest content of heavy elements known to show a transit hinting towards a different
planet-host-star-metallicity relation then the one found by radial-velocity search programs. Finally the properties
of the CoRoT-7b prove that terrestrial planets with a density close to Earth exist outside the Solar System. The
detection of the secondary transit of CoRoT-1 at the 10−5-level and the very clear detection of the 1.7 Earth radii
of CoRoT-7b at 3.5 10−4 relative flux are promising evidence of CoRoT being able to detect even smaller, Earth
sized planets.

And here's the PDF: http://arxiv.org/PS_cache/arxiv/pdf/0912/0912.4655v1.pdf

--Greg

Posted by: siravan Mar 17 2010, 07:11 PM

CoRoT-9b: http://www.nature.com/nature/journal/v464/n7287/full/nature08856.html

"Of the over 400 known1 exoplanets, there are about 70 planets that transit their central star, a situation that permits the derivation of their basic parameters and facilitates investigations of their atmospheres. Some short-period planets2, including the first terrestrial exoplanet3, 4 (CoRoT-7b), have been discovered using a space mission5 designed to find smaller and more distant planets than can be seen from the ground. Here we report transit observations of CoRoT-9b, which orbits with a period of 95.274 days on a low eccentricity of 0.11 ± 0.04 around a solar-like star. Its periastron distance of 0.36 astronomical units is by far the largest of all transiting planets, yielding a ‘temperate’ photospheric temperature estimated to be between 250 and 430 K. Unlike previously known transiting planets, the present size of CoRoT-9b should not have been affected by tidal heat dissipation processes. Indeed, the planet is found to be well described by standard evolution models6 with an inferred interior composition consistent with that of Jupiter and Saturn."

Posted by: Drkskywxlt Jun 14 2010, 08:43 PM

6 new COROT planets announced: http://exoplanet.eu/

COROT-8b is a sub-Saturn mass planet. COROT-10b has a 13 day orbit and high eccentricity. The others are standard Hot Jupiters.

Some more info and a snazzy graphic from CNES:

http://www.universetoday.com/2010/06/14/weird-collection-of-worlds-in-the-latest-cache-of-corot-expoplanets/#more-66357

Posted by: dtolman Jun 28 2013, 01:01 AM

Not sure if this is the right thread, but don't see anything more recent...

Corot mission is officially over - there was a computer failure last November which the probe never recovered from. The official statement came out this week that it will be sent into the atmosphere:
http://smsc.cnes.fr/COROT/GP_actualite.htm#012013

Posted by: dilo Jun 28 2013, 07:34 AM

RIP Corot!

Source: http://smsc.cnes.fr/COROT/PDF/CoRoT_III_programme.pdf