Kepler News and Results

Earth radii of course .Did you see 8 jupiter radii planet in kepler data?I did not

KIC 10905746 b : http://exoplanet.eu/star.php?st=KIC+10905746

KIC 6185331 b : http://exoplanet.eu/star.php?st=KIC+6185331

I don’t understand…
These two candidates are not confirmed (!?)
Why did exo.eu added them ?

Maybe ruling out enough false positives strengthened the case for a planetary nature enough to confirm them in the same sense as Kepler-9d and others were.

But I haven't actually read the paper yet.

Well, Keck was unable to show them false positives (background or grazing binaries etc.) That is not true for most of the Kepler candidates which have only light curve data.

Debra Fischer says the probability they are real is >95%.

arXiv paper, page 5 :

"...Because we do not have an independent measurement
of the mass of the transiting object, KIC10905746 is a
planet candidates rather than a conrmed planet. Photo-
metrically diluted background eclipsing binaries (BGEB)
can have transit depths similar to planets..."

page 7 :
"...We estimate false positive probabilities (FPP) (…) of only 0.3% for KIC 10905746
and an FPP of 5.0% for KIC 6185331..."

Terrestrial, Habitable-Zone Exoplanet Frequency from Kepler
http://arxiv.org/abs/1109.4682

Quote :

Data from Kepler's first 136 days of operation are analyzed to determine the distribution of exoplanets with respect to radius, period, and host-star spectral type. The analysis is extrapolated to estimate the percentage of terrestrial, habitable-zone exoplanets. The Kepler census is assumed to be complete for bright stars (magnitude <14.0) having transiting planets >0.5 Earth radius and periods <42 days. It is also assumed that the size distribution of planets is independent of orbital period, and that there are no hidden biases in the data. Six significant statistical results are found: there is a paucity of small planet detections around faint target stars, probably an instrumental effect; the frequency of mid-size planet detections is independent of whether the host star is bright or faint; there are significantly fewer planets detected with periods <3 days, compared to longer periods, almost certainly an astrophysical effect; the frequency of all planets in the population with periods <42 days is 29%, broken down as terrestrials 9%, ice giants 18%, and gas giants 3%; the population has a planet frequency with respect to period which follows a power-law relation dN/dP ~ P^{\beta - 1}, with \beta = 0.71 +/- 0.08; and an extrapolation to longer periods gives the frequency of terrestrial planets in the habitable zones of FGK stars as \eta_\oplus = (34 +/- 14)%. Thus about one-third of FGK stars are predicted to have at least one terrestrial, habitable-zone planet.

Quote :

It is also assumed that the size distribution of planets is independent of orbital period

Seems a bit dubious this one. E.g. the RV surveys indicate a lack of intermediate period giant planets.

Where are the new kepler candidates these over 1700 published yesterday ?

Kepler-18, a super-Earth and two neptunes in a mean motion resonance. (Think Kepler-9 but Neptunes instead of Saturns).

More specific parameters here.

Edit: arXiv preprint here.

The neptunes c,d are very low density (rather unexpectedly low)super earth b is somehow identical to 55 cancri e

Where did you get that information? If that's true, embargoed
There are currently a total of 8 five planet systems and 2 six planet systems detected by Kepler, so apparently ultracompact and ultraflat systems are not that rare...

I'm curious as to where you got the information, too.

(just wanting to be in compliance with the Embargo Policy)

I feel a little bit anxious when i read that :

http://www.europlanet-eu.org/outreach/index.php?option=com_content&task=view&id=354&Itemid=41

« …The process is called “planet validation,” rather than the usual “planet verification”. Cochran says it’s important to understand the difference – not just for this system, but for future discoveries from Kepler and other missions.
“We’re trying to prepare the astronomical community and the public for the concept of validation,” he says. “The goal of Kepler is to find an Earth-sized planet in the habitable zone [where life could arise], with a one-year orbit. Proving that such an object really is a planet is very difficult [with current technology]. When we find what looks to be a habitable Earth, we’ll have to use a validation process, rather than a confirmation process. We’re going to have to make statistical arguments…”

KOI-135 b and KOI-204 b.

Well, that can't be helped. Many of the Kepler stars are too dim for RV confirmation, even for massive planets. If all the likely sources of false positives can be eliminated, it is very likely they are true planets, especially if we have a large number of candidates.

tommi59 wrote:

Embargoed

I'd really like to see your source!

Unless a publicly available link appears, I'm taking the safe route and removing the information not in compliance with the Embargo policy. I'll restore it if a link shows up. Sorry

/admin mode off

The KOI-### planets are beginning to add up. Hopefully they'll get more aesthetic Kepler-# designations soon.

Don’t worry, Lissauer talked of the system last march
I found a link :
http://www.ibtimes.com/articles/117984/20110302/kepler-finds-strange-worlds-fastest-planet.htm

« …Lissauer says a third system, KOI 500, is one of the most interesting because the planets so closely orbit the parent star. There are five of them, with periods that range from just under a single day to 9.5 days. It resembles Jupiter's system of moons in that regard. Jupiter's three largest inner moons orbit the planet orbit in 1:2:4 resonance, with periods of 1.77, 3.55 and 7.16 days, respectively. KOI 500's planets may have similar characteristics.
If confirmed, the planets around KOI 500 will be in some of the smallest orbits around their star yet found, and the innermost would be bathed in heat from even a relatively cool star. A planet in our own system that orbited the Sun so fast would be only 2 million kilometers from its center -- only a few solar radii from the surface -- and the temperature would be measured in the thousands of degrees Celsius. Standing on the night side of the planet would offer a spectacular view of the other three worlds in the system, as they would all be close enough to show small discs even if they were only the size of Earth… »

Orbital characters of KOI 500 have been public since the first list of Kepler planet candidates was published.

tommi59 listed planet masses, there is no information about them anywhere.

Detection of KOI-13.01 with Orbital Photometry
http://arxiv.org/abs/1110.3510

Kepler KOI-13.01 - Detection of beaming and ellipsoidal modulations pointing to a massive hot Jupiter
http://arxiv.org/abs/1110.3512

Measurement of the Spin-Orbit Misalignment of KOI-13.01 from its Gravity-Darkened Kepler Transit Lightcurve
http://arxiv.org/abs/1110.3514

So no more a vague substellar companion, but a planetary one? Very nice find. A hot Jupiter orbiting an A star and wide binary too.

Weird that the radius is so large despite the apparently high mass (though there does seem to be quite a bit of variation in the estimates). Really have to wonder what is going on with giant planets around intermediate-mass stars, the planetary distributions around giant stars (retired A-stars) has several oddities.

It is also strange EPE treats is as unconfirmed planet. Even the lambda has been estimated!