The Kepler Mission

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robotical

Guest
wOOt! I've been looking forward to this mission ever since it was announced!

If there are any aliens out there, we're looking for you!
 
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Swampcat

Guest
I saw the launch last night on NASA TV. Very smooth countdown. Congrats to ULA and NASA.
 
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qzzq

Guest
Excellent! Let the hunt begin! Congratulations to all involved for a job well done.
 
Q

qzzq

Guest
MeteorWayne":11slwfex said:
Check out the size of the CCD Focal Plane Assembly

kepler-focal-plane-assembly.html

I think you meant this one:

286262main_07-3348d1-Kepler-4x3_946-710.jpg
 
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MeteorWayne

Guest
thanx q, I'm having a difficult time with images.

She's a beauty, huh!
 
D

dragon04

Guest
Dang if I didn't forget about the launch. It HAD to be more interesting than BSG. Which, in and of itself should have reminded me about the launch. And didn't.

I watched the replay on NASA this morning. They showed the launch to just past the SRB Sep. Anyways, I have scoured some sites, and for the life of me, I can't find where Kepler is gonna be parked. All I came up with was that it will be in an Earth-Trailing orbit.
 
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MeteorWayne

Guest
It's actually parked in a 371 day orbit around the sun. So each year it falls about 6 days further behind the earth, Cool, huh?
 
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erioladastra

Guest
Mee_n_Mac":274y6v68 said:
Psymon":274y6v68 said:
Hi

I know next to nothing about astronomy - but from what i have heard, ppl are hunting for planets by watching stars to see if they dim slightly when the planet passes infront of them...

now that seems all good and well, but, isn't it a little presumptious to assume that the plane of the orbit of said planet would line up perfectly with our angle of viewing!!??

Surely solar systems could be at any given angle, so we might be looking 'down' at a system from the 'top', so it's planets would never cross our line of sight?

-Or are we certain that all star systems are orientated the same way?

it just confuses me :[

You are correct in that not all orbits are aligned with the Earth such that the planet transitting it's sun is visible. If you go here and scroll down to Geometric Probability you can see how they've calculated the odds that an alignment will be favorable. So yes there's no guarantee that if there's planets to be found, Kepler will find them ... just due to mis-alignment.

That is why you look at ~ 100,000 stars. Statistically there should be a number that will have the right orientation once you rule out the other orbits, the stars that are too bright, too faint etc.

Now while this is exciting, it is really the tip of the iceberg. Think about it - you will get continuous variability data on 100,000 stars. Even if you never find a planet you will reap phenomonal benefits to astronomy!!
 
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BoJangles2

Guest
after the 3 years is up, do they look at another 100000 stars?
 
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MeteorWayne

Guest
BoJangles2":1p0mkz5k said:
after the 3 years is up, do they look at another 100000 stars?

No, the idea is to spend more time looking at the same stars to capture planets with longer orbital periods, or to refine those already discovered. It takes at least 3 transits to confirm the planetary data is real.

IIRC, they have enough maneuvering propellant to go about 6 years.

Edited, corrected occultations to transits. D'oh!
 
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schmack

Guest
Has Kepler been positioned in it's orbit yet? When will we start seeing the results of it's first observations? I'm keen to know that it's all working the way it's supposed to. It'd be such a dissapointment if this one had glitches the way that Hubble did for it's first round of observations.
 
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MeteorWayne

Guest
schmack":36604tcc said:
Has Kepler been positioned in it's orbit yet? When will we start seeing the results of it's first observations? I'm keen to know that it's all working the way it's supposed to. It'd be such a dissapointment if this one had glitches the way that Hubble did for it's first round of observations.

LOL, you'll have to be a little patient (in fact patience is required for the whole mission)

The Commisioning phase lasts 37 days; in fact the cover doesn't even come off the scope for 3 weeks.
It requires lots of calibrations in order to be able to perform at the required parts per million level.

Then it will take a long time to collect the data. They expect a major release of results about once a year, although if anything interesting pops up, I'm sure they will do something in the interim.
 
S

Simonj

Guest
Psymon":3lwaa11t said:
Hi

I know next to nothing about astronomy - but from what i have heard, ppl are hunting for planets by watching stars to see if they dim slightly when the planet passes infront of them...

now that seems all good and well, but, isn't it a little presumptious to assume that the plane of the orbit of said planet would line up perfectly with our angle of viewing!!??

Surely solar systems could be at any given angle, so we might be looking 'down' at a system from the 'top', so it's planets would never cross our line of sight?

-Or are we certain that all star systems are orientated the same way?

it just confuses me :[

Looks like there is a 1% chance that any orbit is visible from our angle. So with a sample of 100,000 stars, that still leaves 1000 that should be visible.
 
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qzzq

Guest
From the mission homepage: http://kepler.nasa.gov/about/news.html

2009 April 8. Mission Manager Update - The dust cover was successfully jettisoned from the front of the telescope last evening at about 7:18 p.m. PDT. Everything went according to prediction, with the vehicle experiencing a slight push to one side. Kepler's attitude control system easily responded to the movement, steering the spacecraft back to its original position.

Starlight was seen in all four of the fine guidance sensors on the corners of the photometer focal plane (the area where light is focused). The spacecraft was maneuvered to the science attitude, or the position where it will collect science data. It will collect images as the temperatures drop to operational range. The next several days will be spent calibrating the alignment of the fine guidance sensors with the spacecraft star trackers, and achieving fine point using the fine guidance sensors. This will enable the spacecraft to stabilize the line of sight at levels similar to the performance of NASA's Hubble Space Telescope.

April 8 14:00 UTC - Distance to Kepler: 3,153,000 km; 1,959,000 mi; 0.021 AU; 8.20 times the distance to the Moon.

:)
 
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CommonMan

Guest
qzzq":1ik42nlw said:
From the mission homepage: http://kepler.nasa.gov/about/news.html

2009 April 8. Mission Manager Update - The dust cover was successfully jettisoned from the front of the telescope last evening at about 7:18 p.m. PDT. Everything went according to prediction, with the vehicle experiencing a slight push to one side. Kepler's attitude control system easily responded to the movement, steering the spacecraft back to its original position.

Starlight was seen in all four of the fine guidance sensors on the corners of the photometer focal plane (the area where light is focused). The spacecraft was maneuvered to the science attitude, or the position where it will collect science data. It will collect images as the temperatures drop to operational range. The next several days will be spent calibrating the alignment of the fine guidance sensors with the spacecraft star trackers, and achieving fine point using the fine guidance sensors. This will enable the spacecraft to stabilize the line of sight at levels similar to the performance of NASA's Hubble Space Telescope.

April 8 14:00 UTC - Distance to Kepler: 3,153,000 km; 1,959,000 mi; 0.021 AU; 8.20 times the distance to the Moon.

:)

Now the hunt is on. I'm betting in 4 weeks after it really starts looking for planets that it will find one of interest. May not be just like Earth but more habitable than what they have found so far. What do you think? How long?
 
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venator_3000

Guest
[
Now the hunt is on. I'm betting in 4 weeks after it really starts looking for planets that it will find one of interest. May not be just like Earth but more habitable than what they have found so far. What do you think? How long?[/quote]

Well, I would agree that the hunt is on, but remember that this is a photometric survey. So it may take many months or years to detect a dip in a given star's luminosity. Kepler will be looking toward the so-called Kepler Field which is in roughly the constellations of Cygnus and Lyra. If you go out in the summers in the northern hemisphere you can see these constellations, they make up part of the Summer Triangle. That area is along one of the galaxy's spiral arms and consists of about 100,000 observable stars. These stars range from 600 lightyears to 3000 lightyears distance. Less than 1% are closer than 600 lightyears, and anything transitting a star beyond 3000 lightyears won't be observable by the instrument.

Kepler does its observing with a mosaic of CCDs. On this mosaic 2 CCDs form a square module with each of the 21 modules covering about 5 square degrees of the sky. Each CCD is about 3x6 cm in size. This is a very large field of view, even compared to what Hubble can collect. it will also take time to crucnch through this data.

Remember, Kepler is looking for transits. These are dips in the luminosity of a given star caused by a planet passing in front of it. Assuming the ecliptic plane of a possible target star is in line with Kepler, the transits will take time to measure and detect. Not all of the stars in the kepler Field will be oriented this way. Many potential targets will be lost if we are looking down on a star's ecliptic. If Earth serves as a model we revolve around the Sun every 365 days. If the line-up is right Kepler might only see a possible transit of a given planet over just a few days, then a follow-on observation might be needed to confirm the first transit. That could take awhile, despite the fact that in the decade leading up to this mission many ground-based telescopes have participated in mapping the Kepler Field and have even done some initial photmetric measurements. Indeed, the mosaic technique in the Kepler camera had many, smaller, "grandfather" cameras. Some of these were used around the world to both test the hardware and also map the field.

In a sense Kepler is a scout for a more advanced telescope, like the planned Terrestrial Planet Finder. It will scout out potential targets and other telescopes, either in space or Earth-based, will look at these candidates. Even if a telescope were to image a pale blue dot around another star the spectroscopy from such a planet would tell us volumes about conditions and even potential for life on these other stars.

Still, it is a lot of detective work but a very exciting mission.

V3K
 
C

CommonMan

Guest
venator_3000":23obuhxy said:
[
Now the hunt is on. I'm betting in 4 weeks after it really starts looking for planets that it will find one of interest. May not be just like Earth but more habitable than what they have found so far. What do you think? How long?

Well, I would agree that the hunt is on, but remember that this is a photometric survey. So it may take many months or years to detect a dip in a given star's luminosity. Kepler will be looking toward the so-called Kepler Field which is in roughly the constellations of Cygnus and Lyra. If you go out in the summers in the northern hemisphere you can see these constellations, they make up part of the Summer Triangle. That area is along one of the galaxy's spiral arms and consists of about 100,000 observable stars. These stars range from 600 lightyears to 3000 lightyears distance. Less than 1% are closer than 600 lightyears, and anything transitting a star beyond 3000 lightyears won't be observable by the instrument.

Kepler does its observing with a mosaic of CCDs. On this mosaic 2 CCDs form a square module with each of the 21 modules covering about 5 square degrees of the sky. Each CCD is about 3x6 cm in size. This is a very large field of view, even compared to what Hubble can collect. it will also take time to crucnch through this data.

Remember, Kepler is looking for transits. These are dips in the luminosity of a given star caused by a planet passing in front of it. Assuming the ecliptic plane of a possible target star is in line with Kepler, the transits will take time to measure and detect. Not all of the stars in the kepler Field will be oriented this way. Many potential targets will be lost if we are looking down on a star's ecliptic. If Earth serves as a model we revolve around the Sun every 365 days. If the line-up is right Kepler might only see a possible transit of a given planet over just a few days, then a follow-on observation might be needed to confirm the first transit. That could take awhile, despite the fact that in the decade leading up to this mission many ground-based telescopes have participated in mapping the Kepler Field and have even done some initial photmetric measurements. Indeed, the mosaic technique in the Kepler camera had many, smaller, "grandfather" cameras. Some of these were used around the world to both test the hardware and also map the field.

In a sense Kepler is a scout for a more advanced telescope, like the planned Terrestrial Planet Finder. It will scout out potential targets and other telescopes, either in space or Earth-based, will look at these candidates. Even if a telescope were to image a pale blue dot around another star the spectroscopy from such a planet would tell us volumes about conditions and even potential for life on these other stars.

Still, it is a lot of detective work but a very exciting mission.

V3K[/quote]

Sounds very time comsuming. I haven't had time to read all about the mission yet, so I just got excited. Guess I should chang my bet from 4 weeks to 4 years.
 
3

3488

Guest
Now that the dust cap has been jetissoned, it will take some time for the photometers to be properly calibrated.

What we do know was that the Delta 2 had provided such a smooth ride for Kepler that the instruments are in tip top condition, no anamolies have been detected & there appears to be no problem with any of them being able to conduct this mission & a possible extended one without incident.

The region between Cygnus & Lyra will hopefully reveal what Kepler is looking for. There are more than enough stars in that part of the Milky Way to do so.

The main issue of course is how many of them will have Sol on their ecliptic, a necessity for transiting planets to be detected?

I suspect Kepler will find gas giants first, hot Jupiters, hot Neptunes, etc, but then hopefully smaller fry like super Earths, Earths, Mars or even Mercurys may show (apparently Kepler can detect planets smaller than Mercury orbiting sunlike stars & smaller).

It will be great to see some calibration results & images.

Andrew Brown.
 
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MeteorWayne

Guest
Excellent news. Let the science begin!
Thanx for catching that announcement Andrew.
 
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qzzq

Guest
MeteorWayne":1l0nkilp said:
Excellent news. Let the science begin!
Thanx for catching that announcement Andrew.

You're welcome... :roll:
 
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MeteorWayne

Guest
Sorry bout that! For some reason my last unread post link missed a whole page. Boy is my face red! :oops:
 
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Mee_n_Mac

Guest
MeteorWayne":3p9ypzis said:
Sorry bout that! For some reason my last unread post link missed a whole page. Boy is my face red! :oops:
]

FWIW I get the same thing from time to time. I can't correlate the happening to anything but at least once a week I'll discover posts that I somehow missed. That said I'm not complaining, it still feats the buck out of Pluck !
 
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rocketscientist327

Guest
This is such an exciting mission! The first pictures are more spectacular that I could have imagined.

I am really looking forward to finding new planets. It will be awesome.

VR
RS327
 
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