hi,

kepler ll find a planet only if the planer passes between the kepler's field of view and the star...

but i think that the possibility for a planet to orbit its star at a certain degree is very very low, because there are so many other possible orbits.

to make things clear, see this image: Kep
i m not good at drawing, but i think its understandable

in the picture, case 1(above) is the setup we need to detect a planet... but planets may circle around as in case2(below) too. so its impossible to detect it

so, kepler will b finding only a fraction of planets, that it cud see and not all of them...

if i m wrong, pls expain me... also pls tell me how to add image to this post(i tried [img] but its not working)

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SAIYASODHARAN
Known Is Drop, Unknown Is Ocean

hi,

kepler ll find a planet only if the planer passes between the kepler's field of view and the star...

You are correct. The transit method is just one of a few different ways to detect an extrasolar planet.

Multiple methods help track elusive quarry, HTML version
4 Ways to Find a Planet, interactive Flash presentation

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me@rescam.org

hi,

kepler ll find a planet only if the planer passes between the kepler's field of view and the star...

but i think that the possibility for a planet to orbit its star at a certain degree is very very low, because there are so many other possible orbits.

to make things clear, see this image: Kep
i m not good at drawing, but i think its understandable

in the picture, case 1(above) is the setup we need to detect a planet... but planets may circle around as in case2(below) too. so its impossible to detect it

so, kepler will b finding only a fraction of planets, that it cud see and not all of them...

if i m wrong, pls expain me... also pls tell me how to add image to this post(i tried [img] but its not working)

Actually it's not a big fault...it's really the only way we have at this time to detect planets as small as Earth. The designers of Kepler understood this and already figured out that the odds of everything being lined up properly is only about one half of one percent (0.5%). However, given the sheer number of stars that Kepler will be looking at, that still adds up to nearly 500 Earth-like planets. Hardly a fault at all. :)

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You will be assimilated...bunghole!

Kepler night launch

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me@rescam.org

Did you have to title your post in that manner so soon after launch? I thought the spacecraft broke.

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The chances are pretty small that the planet will transit its star as seen from Kepler. In the case of something like the Earth, it's about 1/2 degree divided by 180 degrees or about 0.28%. But that's probably why Kepler has been set up to look at over 100,000 stars. Out of 280 possible stars there might be several candidates. It'll probably have to make a lot of measurements because transit times are short.

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thanks everybody for explaining the things to me... but i m very disappointed on knowing that only a small no. of planets cud be detected by kepler... but it okay, there is no other way...

and MRay. i m sorry. the next time i ll keep the title in a more suitable way.

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SAIYASODHARAN
Known Is Drop, Unknown Is Ocean

thanks everybody for explaining the things to me... but i m very disappointed on knowing that only a small no. of planets cud be detected by kepler... but it okay, there is no other way...

and MRay. i m sorry. the next time i ll keep the title in a more suitable way.

Once Kepler returns with results, we can build larger space telescopes and interferometers which will be able to actually photograph these planets. Once the new equipment has checked out Kepler's results, we can point it at any star and view the planets there visually without needing any transits. :) One step at a time.

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You will be assimilated...bunghole!

Just playing with the idea, would it perhaps make sense to pay special SETI attention to the directions this Kepler possibly reveals in the future years?

Regards

PK

Well the only way to get the Seti community focused on one of these new planets is if we confirm that there are biological processes going on. If we find evidence life, then I'll bet every telescope in the world will be pointed in that direction to see if it's simple or advanced life.

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You will be assimilated...bunghole!

Engineers have begun to check Kepler to ensure it is working properly, a process called "commissioning" that will take about 60 days. In about a month or less, NASA will send up commands for Kepler to eject its dust cover and make its first measurements.

Well, that is quite thoughtful of them. To contribute more space debris!

"Even if we find no planets like Earth, that by itself would be profound. It would indicate that we are probably alone in the galaxy," said Borucki.

That would indeed be profound since we can't see stars inside nearby galaxy. Speaking of which, can Kepler see stars on the opposite side of Milky Way? Past its centre? I suppose not.

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Life is short so, make the best of it.

Any Earth-size planets orbiting in the habitable zones of stars the size of our Sun would take at least three years to be confirmed.

Now, how did they come to that conclusion? It takes 3 years to confirm.

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Life is short so, make the best of it.

Now, how did they come to that conclusion? It takes 3 years to confirm.

In order for Kepler to confirm the presence of a planet, it needs to observe three transits. Earth takes one year to go around the sun. Thus, if an alien Kepler were looking at us, they'd need to wait three years for us to go around our sun three times.

Most Earthlike planets are expected to be around the same distance from their stars as we are from ours. So about three years.

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You will be assimilated...bunghole!

In order for Kepler to confirm the presence of a planet, it needs to observe three transits. Earth takes one year to go around the sun. Thus, if an alien Kepler were looking at us, they'd need to wait three years for us to go around our sun three times.

Most Earthlike planets are expected to be around the same distance from their stars as we are from ours. So about three years.

Strange, I thought Kepler is looking at a particular part of the Milky Way that is unaffected by Earth orbit about the Sun. Hence, looking at the same spot without blinking for 3 years?

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Life is short so, make the best of it.

In order for Kepler to confirm the presence of a planet, it needs to observe three transits. Earth takes one year to go around the sun. Thus, if an alien Kepler were looking at us, they'd need to wait three years for us to go around our sun three times.

Most Earthlike planets are expected to be around the same distance from their stars as we are from ours. So about three years.

Strange, I thought Kepler is looking at a particular part of the Milky Way that is unaffected by Earth orbit about the Sun. Hence, looking at the same spot without blinking for 3 years?

I think you missed the point.

If the planet we are trying to detect has a "year" the same length as ours, it would take 3 yrs for it to transit it's own sun three times.

Ah, forgive me for reading too fast. But why 3 transits are needed?

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Life is short so, live it well.

Ah, forgive me for reading too fast. But why 3 transits are needed?

Only my guess but I would think you need 3 so that you can compare timing between 1-2 and 2-3 to verify that you are observing a constant orbital rate.

Ah, forgive me for reading too fast. But why 3 transits are needed?

Only my guess but I would think you need 3 so that you can compare timing between 1-2 and 2-3 to verify that you are observing a constant orbital rate.

Another reason:

If there are multiple planets orbiting/transiting the same star, the intervals between transits will vary. Therefore you need a minimum of 3 detections to validate a single planet and 6 to verify a second.

Ah, forgive me for reading too fast. But why 3 transits are needed?

In order to make sure there's really something there. In theory, a single transit could be "faked" by having some kind of object pass between Kepler and the target star. By observing three full transits, it can be determined whether or not they are the real thing or just false alarms. As a prevoius poster mentioned, if you compare the orbital timing, and find three transits that have a nearly identical period, then it's safe to assume it's not a false alarm.

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You will be assimilated...bunghole!

I think you missed the point.

If the planet we are trying to detect has a "year" the same length as ours, it would take 3 yrs for it to transit it's own sun three times.

Actually we could get results in two years from observations begin.
The first transit now, the second in a year, and the third in two years :-)

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