NASA's Kepler Planet Finding Mission makes its first discovery announcement.
Announcement on NASA TV, from www.nasa.gov at 2pm thursday 6th of August, 2009.
Now with figures and press release info.
UPDATE: Kepler Early Results Press Release.
And, they're off... the announcement, as rumoured is what they could squeeze out of the calibration data.
In particular, calibration suggests photometry is good enough, and stable enough - at least over month time scales, and hopefully longer - that Kepler will have sensitivity to find Earth sized planets, at least for the less luminous stars.
Relative photometry for HAT-P-7 (click to embiggen)
They calibrated off HAT-P-7 - a known transiting hot jovian in the Kepler field.
Relative photometry curve looks pretty inpressive.
Good old: "our errors are less than the witdh of the line we used to plot it".
They're seeing secondary transit, and sensitivity, for this short period planet, is good enough and stable enough that the Kepler team are happy.
Two other already known transiting planets in the Kepler field are also seen.
Secondary transit - showing photometric noise of ~ 100 ppm (click to embiggen)
Kepler is a medium sized NASA mission, looking for low mass transiting planets orbiting relatively nearby stars.
Kepler basically sits and stares ate a fixed patch of the sky, looking for periodic dimming of individual stars as planets cross in front of the stars on their orbits, for those rare instances in which the orbit is almost exactly edge-on to our line of sight.
From the number of planets found, and knowing the orbital geometry, Kepler will provide good statistics on the abundance of planetary systems in the galactic neighbourhood, for stars with masses from about that of the mass of the Sun to about half that mass, and for orbital periods shorter than about a year.
Kepler ought to be sensitive to planets in the habitable zone of K-stars, and may be able to see planets with masses as low as Earth mass, for the lowest mass stars it can reliably observe, if the instruments work to specification or better.
Kepler is almost six months into its mission, and the early data has been analyzed.
Most of the candidate systems have not been followed up, and most will require independent confirmation, preferably through determination of radial velocity variation of the star by observing the Doppler shift of the star's spectrum with ground based high resolution spectrographs, observing for extended periods over a long baseline, using the largest possible telescopes.
So, the most interesting stuff will take time to confirm.
They confirm that followups on candidate detections are in process and they expect to have announcements of confirmed discovery for short period low mass planets in early 2010 (watch for AAS Jan meeting announcement, I guess).
In about 2012 they can talk about any confirmed detections for (near)earth mass planets in longer period orbits, going up to one year orbits.
If I had to guess, I'd say watch for 1-few Earth mass planets in month-year orbits around KV stars - that is likely to be their hot discovery space.
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Yay! I pointed to your blog on Facebook.
Is there any reason to believe that three-day terrestrial planets will be rarer than three-day giants?
hm, well, depends...
if we understood the physics of migration, and we don't, then you can argue that either short period terrestrials ought to be very rare, or extremely common, depending on some assumptions
I was an author on a paper which argued that there ought to be some short period Earths/SuperEarths, and provided a physical reason why
I'll be interested to see if it works.
I'd bet that superearths are extremely common. I can't believe how well they measure the secondary eclipse. I wish Kepler could slew and point at other objects :)
When I asked about about pointing Kepler at other objects (because I was disappointed that nearby 61 Cygni was almost but not quite in the Kepler star field), Deputy PI David Koch graciously took time out to write back. There were various reasons why slewing Kepler isn't in the cards (they will always want more data from the Kepler star field, they designed it to look at stars between the 9th and 15th magnitudes - perhaps ruling out 5th magnitude 61 Cygni), but Mr. Koch also said something that completely surprised me: "The hardware is specifically designed for the Kepler star field. The angle on the sunshade is cut for 55 deg ecliptic lat and the rotation of the focal plane relative to the solar panels was set for the location of bright stars."
Steinn,
Do you give out reprints?
Got to wonder what else will crop up in the light curves. Transiting circumbinary planets would be neat. As would detections of moons.
Technically I give out reprints, but for any paper less than 12-15 years old, I'd just be going to arXiv or ApJ and grabbing the same pdf as anyone else. Couple of the older ones are not on arXiv, everything else should be.
5th mag star ought to saturate the detectors and photometry would actually suck, I'd think.
I hadn't noticed that Kepler was cut to fit, as it were. Neat.
BTW: in case Ames is still reading - I got the word that absolutely no interesting stuff will be leaked before official word is due out.
I won't...
Two questions:
1. Will Kepler be able to detect almost-but-non-transiting hot Jupiters from rising and falling light curves due to their phases (like HAT-P-7b only without the transit dips).
2. Will Kepler be able to detect the presence of other, non-transiting planets from variations in the timing of the transits of planets that do cross in front of the host star?
I can imagine the second one in particular would be useful in characterizing solar systems better, if it was possible.