Kepler Mission Options

[JGodbaz]

Got to wonder what 'no star apparent at target location' really means.

Some very interesting papers there, especially considering how little Kepler data it was based on.

[Syrinx]

Seven more papers up on ArXiv today. A couple of them appear to be Kepler-related.

[Paolo]

in Science Express today:
Kepler Planet-Detection Mission: Introduction and First Results

[Syrinx]

Paolo, access to that article costs $15. Does it contain any new information, or is it a rehash of information we have access to via other means? From the abstract it seems like nothing new.

[siravan]

The Science paper is essentially a summary of the method for detection and verification of the exoplanets and the properties of the four new ones presented in the press conference and arxiv papers. One issue that I had missed in other sources was: "The stars associated with the Kepler exoplanets are generally larger than those shown in the Exoplanet Encyclopedia for transiting planets (Fig. 2). The difference could be due to the Malmquist bias or to the preferential selection of stars with sharp spectral lines for the Kepler follow-up; i.e., slightly evolved stars."

[Greg Hullender]

Don't miss the supplemental materials, which have a wealth of information on things like how they filter out false positives (most were eclipsing binary stars), how they measure star size and mass, etc. http://www.sciencemag.org/cgi/content/full...nce.1185402/DC1

The original paper has some nice graphs in it too, comparing Kepler results with previously-known planets. Surprisingly, they didn't find any super-short-period planets -- nothing under a day and a half -- even though such planets would have been the very easiest to discover (they don't need such precise alignment to give transits). No speculation on why this is though.

Figure 3 shows evidence that gas giants and ice giants actually form two clusters -- that there's isn't a smooth continuum of planet sizes. Three clusters, if you count rocky planets like Earth, although that's extrapolating from two data points. (And from the absence of points in between, of course.)

I wonder if they're really going to make us wait a whole year for another taste?

--Greg

[Hungry4info]

IIRC, they load up all the planets they got and dump them onto the public every six months.

[nprev]

That's kind of an awesome thought in its way, isn't it?

[Hungry4info]

Yeah, and with there being a finite number of easy-to-catch hot Jupiters, the bi-anually reports will only get better each time as longer and longer period planets are tracked down. (not to mention planets of lower and lower mass)

[Greg Hullender]

Possible failure in a module that holds two of the CCDs reported in the latest update:

http://www.kepler.arc.nasa.gov/news/mmu/in...s&NewsID=22

" . . . The possible loss of the module represents a loss of five percent of the Kepler Field-of-View. . . . The module will remain offline pending further trouble-shooting and analysis. In the event the module functionality cannot be restored, Kepler still is expected to fully meet its mission goals for detecting Earth-size planets in the habitable zone of other stars."

--Greg

[belleraphon1]

Observations of Transiting Hot Compact Objects (by KEPLER)

"Kepler photometry has revealed two unusual transiting companions orbiting an early A-star and a late B-star. In both cases the occultation of the companion is deeper than the transit. The occultation and transit with follow-up optical spectroscopy reveal a 9400 K early A-star, KOI-74 (KIC 6889235), with a companion in a 5.2 day orbit with a radius of 0.08 Rsun and a 10000 K late B-star KOI-81 (KIC 8823868) that has a companion in a 24 day orbit with a radius of 0.2 Rsun. We infer a temperature of 12250 K for KOI-74b and 13500 K for KOI-81b. We present 43 days of high duty cycle, 30 minute cadence photometry, with models demonstrating the intriguing properties of these object, and speculate on their nature. "

http://fr.arxiv.org/PS_cache/arxiv/pdf/1001/1001.3420v1.pdf

VERY COOL er HOT!

Craig

[Habitable Zoner]

Could the next announcement of planet discoveries (presumably still hot Jupiters, but possibly even hot superearths) come as early as next month, at the Amercian Physical Society meeting in Washington, DC? Most of the abstract (below) is old news, but the end ("discoveries of several new exoplanets are shown") is vague enough that new discoveries could be included. Does anyone have any insight on this?

From APS Meeting 2010

Session V1: Plenary Session III

Tuesday, February 16, 2010
9:06 AM–9:42 AM

William J. Borucki
(NASA Ames Research Center)

Kepler is a Discovery-class mission designed to determine the frequency of Earth-size planets in and near the habitable zone of solar-like stars. The instrument consists of a 0.95 m aperture photometer designed to obtain high precision photometric measurement of > 100,000 stars to search for patterns of transits. The focal plane of the Schmidt-type telescope contains 42 CCDs with at total of 95 megapixels that cover 115 square degrees of sky. The photometer was launched into an Earth-trailing heliocentric orbit on March 6, 2009, finished its commissioning on May 12, and is now in the science operations mode. During the commissioning, data were obtained at a 30 minute cadence for 53,000 stars for 9.7 days. During the first 33.5 days of science-mode operation, 156,000 stars have been observed. Discoveries based on these data are presented. Although the data have not yet been corrected for the presence of systematic errors and artifacts, the data show the presence of hundreds of eclipsing binary stars and variable stars of amazing variety. To provide some estimate of the capability of the photometer, a quick analysis of the photometric precision was made. Analysis of the commissioning data also show transits, occultations and light emitted from the known exoplanet HAT-P7b. The data show a smooth rise and fall of light from the planet as it orbits its star, punctuated by a drop of 130$\pm$11 ppm in flux when the planet passes behind its star. We interpret this as the phase variation of the dayside thermal emission from the planet plus reflected light as it orbits its star and is occulted. The depth of the occultation is similar in amplitude to that expected from a transiting Earth-size planet and demonstrates that the Mission has the precision necessary to detect such planets. Discoveries of several new exoplanets are shown and compared with known exoplanets with respect to mass, size, density, and orbital period. Detection of stellar oscillations and unusual objects are also presented.

[Greg Hullender]

No, I'd expect that this will just be a refinement of data we've already heard about. I guess it's vaguely possible that that refinement itself will have uncovered new planets, but from the tone of the abstract, I wouldn't expect it.

Would LOVE to be wrong, of course. :-)

--Greg

[Habitable Zoner]

Then maybe, just maybe, our next opportunity will be March 29 at the Exoplanets Rising: Astronomy and Planetary Science at the Crossroads conference in Santa Barbara. I don't see any abstracts posted yet, but there are 45 minutes scheduled for a talk by Bill Borucki (NASA/Ames) entitled "Status of Kepler Results." One can hope.

[siravan]

Another safe mode on February 2: http://www.nasa.gov/mission_pages/kepler/n...m-20100208.html