From the Borucki et al. paper:

"Summary and Conclusions
The Kepler results imply that;
1) Most candidate planets are significantly smaller than Jupiter.
2) There is a broad maximum in the frequency of candidates with orbital period in the range
from 2 to 5 days. This peak is more prominent for large candidate planets than it is for small
candidates.
3) The measured occurrence frequencies of Super-Earth-, Neptune-, Jupiter-, and Super-
Jupiter-size candidates in short period orbits are 2.5x10-3, 1x10-3, 0.9x10-3, and 2.x10-4,
respectively.
4) The distributions of orbital period and magnitude of the candidates larger than Jupiter
appear to be quite different from those of smaller candidates and might represent small stellar
companions or errors in the size estimation of the dimmest stars in the Kepler planet search
program.."

"706 targets from this first data set have viable exoplanet candidates with sizes as small as that of the Earth..." Hot earths, to be sure, but this is a stunning validation of the mission already!

New on arXiv: David S. Spiegel, Adam Burrows. "Atmosphere and Spectral Models of the Kepler-Field Planets HAT-P-7b and TrES-2" arXiv:1006.1660v1

Another Kepler lecture for the general public in the SF Bay area: Jack Lissauer at the Randall Museum, July 21 from 7:30 - 9:00 pm. (See here for details.)

Seems like they should schedule a press conference for next Tuesday. If they don't, they'll be missing a great opportunity to grab some headlines!

No Kepler "news" at the Miami AAS meeting, but it's nice to see that Jonathan Fortney of the Kepler team was awarded the 2010 Harold C. Urey Prize in Planetary Science...

I checked when Bill Borucki has time scheduled on the HIRES instrument at Keck during the next couple of months, where I believe most of the high-resolution radial velocity measurements will be made. Here's the schedule:

• Tue, May 25 through Thu, May 27;
• Mon, Jun 29 through Thu, July 1;
• Sat, July 24 through Mon, July 26

Just in case anyone else thinks such things are interesting...

Thanks for the report.


Sweet! I hope it happens. Waiting until January seemed so conservative. Surely by the end of this ground observation season, there will be something well into the publication pipeline--another batch of short period hot jupiters, if nothing else...

I'm resigned to no new Kepler discovery announcements until January 2011. However, there may still be some interesting discussion and perhaps independent analysis of prior results at a few major conferences this summer. Here are some to keep an eye on:

• COSPAR Meeting: "Extrasolar Planets: Recent Results from Space Missions and Future Prospects" July 18-25 (overview)
  
• 2010 Sagan Exoplanet Summer Workshop: "Stars as Homes for Habitable Planetary Systems" July 26-30, 2010 (agenda)
  
• Observatoire de Haute-Provence: "Detection and Dynamics of Transiting Exoplanets" August 23-27 (program)

Ah, thanks. That clears things up a lot. So I guess if they have a "short list" by now, it's probably very incomplete, since two transits are required. They've seen everything with an orbital period of 4-5 months transit at least twice. Some planets with periods as long as 9-10 months could have been observed twice, if Kepler was lucky enough to have them transit during the first month of data gathering...

I think with even a single transit, one could get a rough back-of-the envelope estimate of the period, right? If you assume a near-circular orbital geometry and have a decent idea of the diameter of the star, you should be able at least to estimate the period well enough to place the exoplanet reasonably well within its planetary system. You could tell whether it was probably a "hot" planet, a potential habitable zone planet, or a "cold" planet that you caught making a rare transit. And a single transit curve could also give you a decent idea of the planet's size, again if you make some reasonable assumptions. You could at least tell whether you were looking at a likely Jupiter, Neptune, or super-Earth.

Of course the three-transit gold standard, with radial velocity confirmation if possible, would still be required before any announcement. But if I'm thinking right, then of their 200-300 "candidates," they probably already have a short list of potential headline-grabbers.

Are my understanding and reasoning correct here? Thoughts?

Thanks!

10 years is huge. We should be able to see any earth-sized or larger planet up to nearly 2 AU from each star. That will give us extremely valuable insights into these systems.

How I do wish that there was at least one large scope located far enough north that the star-field would be circumpolar. Too late now, but wouldn't there be some location in the northern USA with good enough climate and elevation and dark enough skies for a serious research scope? Wouldn't it have been great if construction of a dedicated follow-on instrument would have been part of the original Kepler proposal? Maybe it would be coming online right about now. Nah--with all the red tape, probably not.

Also new on arXiv: the discovery of a nova-like cataclysmic variable star in the Kepler data (here). Stare unblinkingly at a field of stars and you'll see all kinds of interesting things...

Great! Please pass on your observations and impressions from the talks. Thanks.

Borucki is giving a talk at Stanford in a few days: "Status of the Kepler Mission and Early Discoveries." (Tuesday, April 27, 2010. 4:15-5:45 PM). It's free and open to the public. Of course there won't be any new revelations in that kind of venue, but folks in the area might be interested in attending and plying him with questions, just for fun. The event website, such as it is, can be found here.

400 "objects of interest" plus 328 more "candidates"? News story here.

ADMIN: fixed broken link

Wondering if anyone would care to brainstorm a bit...

Let's say that at the end of the Kepler extended mission, there have been 10 planets of 1-1.5 x earth mass discovered in potentially habitable zones around stars in the sample. What kind of follow up would you propose if:

(1) You were the PI of a grant for a few hundred million dollars?

(2) Bill Gates (or better yet, a space agency) asked you to administer a $5-10 billion fund for further researching these planets?

In his talk earlier this week, Borucki understandably dodged a big question (Do you have any candidates that you know to be multi-planet systems?) with "we see all sorts of interesting signals." He also spoke of being able to do a very rough estimate of orbital period using transit times. Reading between the lines, I suspect they're actually feeling very good that they've hit paydirt already with interesting systems--including those with multiple planets, some of them at cool temperature, orbiting a star. But they are going to err on the side of caution. I would, too. The last thing anyone needs is to lose credibility with a headline grabbing announcement that turns out to be just a false positive. (Remember cold fusion?)

Still, if I were going to guess at the discovery announcement timeline, I'd predict (1) many more hot jupiters and neptunes, similar to the first five, later this spring; (2) hot super-earths and temperate gas giants by January 2011; (3) super-earths in habitable zones before the end of 2011; (4) earths in habitable zones before the end of the primary mission.

Not that I take my own speculation all that seriously. Just having fun with it.

Nothing new in terms of "announcements." He did present data on an apparent sixth planet as an example of how careful they have to be in follow-on observations. (In this case, there was a star in the background that was impossible to separate out by the Kepler instrument.) He said they are close to announcing this planet, though. He threw out a lot of teasers about how many "interesting signals" they are seeing, but of course didn't give direct answers to questions about unpublished data. If you're familiar with the data presented at the January AAS, then you might just want to fast forward the first 30 minutes of the presentation and only watch the Q&A session during the last 15 minutes. Some of the questioners were actually discussing unpublished work (in press, I think) about the anomaly of putative planets being hotter than their star, and Borucki commented that they're seeing a lot more than two of those. I'm assuming that the next exoplanet discovery announcements will come at the 216th AAS Meeting in Miami the last week of May. The timing and venue both seem right: another six weeks or so of follow on observations, plus a month to write up papers and get them safely in the publication pipeline before disclosing the data.

Bill Borucki's talk at the Exoplanets Rising conference this morning, "Status of Kepler Results," is already online here. I'm only about 5 minutes into the talk, but it appears to be mostly (if not entirely) a summary of what was already presented in January. Although someone besides me might enjoy watching it, too.

What ground-based scopes actually are involved in checking Kepler observations? Is there a list somewhere?

This statement also caught my eye: "The science team has just begun the follow-on observing season for 2010. At this time, the Kepler star field is visible for about one hour just before dawn. The Kepler star field will be visible for several months from the Earth’s northern hemisphere." Are they saying that they can only perform follow-on observations for a few months out of the year? Is observation from the southern hemisphere not possible?

Understood. But I personally would feel that the discovery of numerous hot super-earths would be monumental. And I am chomping at the bit to hear about earth-sized or smaller planets being detected, regardless of the orbit. That announcement could could certainly come during the first half of this year, perhaps at the May AAS meeting. And while earth-like planets in earth-like orbits are certainly the gold ring, it is conceivable that a (super)earth in a habitable zone around a dimmer star could be discovered by the end of 2010, a year and a half after Kepler's first light. For example, a planet circling a star with half the sun's mass could have a two-month orbit and still fall within that star's habitable zone. I'd say the odds of headline-grabbing results during the next three months and again within the next nine months are quite good.

I asked an attendee at the APS conference if she had attended the Borucki talk on Kepler yesterday, and here was her reply: "I didn't see the talk myself, but from what I heard it was a summary of recent Kepler work - no new results." We'll try to be patient--certainly more at the AAS 216 meeting in Miami 23-27 May 2010, if not before.

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.