Kepler22b-first exoplanet found in hab-zone of sun-like star

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Drakkith said:
Which searches are you referring to?

As I understand it I'm referring to the typical method sometimes called "doppler". It does not require that we see the system edge on. The planet does not have to pass "in front" of the star.
What I'm talking about is the method used for example by Geoff Marcy and Paul Butler in the exoplanet discoveries of the 1990s and subsequently by them and co-workers.

Sometimes also called "radial velocity" method. I'm puzzled by your question since you are involved in exoplanet search---although your search involves the other main technique (the dip in the lightcurve when the planet passes in front.)

Maybe I've said something unclearly and miscommunicated. Let me know if it's still unclear what I'm talking about.

I looked back and thought maybe it was confusing to use uppercase to emphasize the word TRANSIT. So I changed it to *transit* in red. I want to show that my comment refers to where ChrisPhy used that word in his post.
It is important to make clear that at least until recently most of the exoplanet discoveries did NOT use the detection of a transit by dip in the lightcurve. The predominant method was picking up the star's wobble by doppler spectroscopy.
 
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marcus said:
Sometimes also called "radial velocity" method. I'm puzzled by your question since you are involved in exoplanet search---although your search involves the other main technique (the dip in the lightcurve when the planet passes in front.)

Maybe I've said something unclearly and miscommunicated. Let me know if it's still unclear what I'm talking about.

Yeah, I was confused by this:

About *transit*, searches like this one do not require transit.

The sentences after this didn't seem to add up to what you just said. IE they aren't about transit.
 


Sorry about the confusion. Well do you understand now? What I should have said to ChrisPhy was probably something like "About your using the word *transit* in your post, about detecting exoplanets in the 40 nearest stars, it shows you have a mistaken idea about the technique used. I'll try to correct that. Until recently at least most exoplanets were not found by observing a transit..."

Anyway,...:-(

But did you look at the 2011 paper by Mayor et al?
http://arxiv.org/abs/1109.2497
It uses doppler wobble, and it's great.
Though not an expert, and not folowing exoplanets closely, I't say it represents the first real statistics on the prevalence of the mediumsized planets. the super-earth and neptune class.

It's remarkable they came up with a 50% figure for sunlike stars (ie FGK and single).
 
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Is it possible to find out if kepler is solid or gaseous or is that something that our instruments cannot now detect.
 


bobsmith76 said:
Is it possible to find out if kepler is solid or gaseous or is that something that our instruments cannot now detect.

Not with the Kepler data. It will require further observation with different instruments. If we can determine it's mass that should allow us to make a reasonable guess. Although if it's only 2 1/2 times the size of Earth, it's reasonable to assume it isn't a gaseous planet. I think at least.
 


But do we have those instruments available to us now, or do we need to invent new technology in order to get that data?
 


bobsmith76 said:
But do we have those instruments available to us now, or do we need to invent new technology in order to get that data?

I think we can get a lot of it, we just have to wait for more orbits, which takes time.