Kepler Mission |
Kepler Mission |
Sep 24 2005, 04:23 PM
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#1
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Member Group: Members Posts: 147 Joined: 3-July 04 From: Chicago, IL Member No.: 91 |
This NASA Discovery mission is to be launched in June 2008 and will search for Earth-size and smaller planets. Launch was originally scheduled in 2007 but delayed by 8 months due to "funding constraints".
Here's the official web site: http://www.kepler.arc.nasa.gov/ |
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Dec 12 2005, 04:02 PM
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#2
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Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Paper: astro-ph/0512251
Date: Fri, 9 Dec 2005 16:01:29 GMT (988kb) Title: The Effect of the Transit of Venus on ACRIM's Total Solar Irradiance Measurements: Implications for Transit Studies of Extrasolar Planets Authors: G. Schneider, J. M. Pasachoff and R. C. Willson Comments: Accepted to ApJ 8 Dec 2005; 14 pages of text, 8 figures, 1 table \\ We used the 8 June 2004 transit of Venus (ToV) as a surrogate to test observing methods, strategies and techniques that are being contemplated for future space missions to detect and characterize extrasolar terrestrial planets (ETPs) as they transit their host stars, notably NASA's Kepler mission planned for 2008. As an analog to "Kepler-like" photometric transit observations, we obtained (spatially unresolved) radiometric observations with the ACRIM 3 instrument on ACRIMSAT to follow the effect of the ToV on the total solar irradiance (TSI). Contemporaneous high-resolution broadband imagery with NASA's TRACE spacecraft provided, directly, measures of the stellar (solar) astrophysical noise that can intrinsically limit such transit observations. During the ~ 5.5 h transit, the planet's angular diameter was approximately 1/32 the solar diameter, thus covering ~ 0.1 of the stellar surface. With our ACRIM 3 data, we measure temporal changes in TSI with a 1 sigma per sample (unbinned) uncertainty of approximately 100 mW m^-2 (0.007%). A diminution in TSI of ~ 1.4 W m^-2 (~ 0.1%, closely corresponding to the geometrically occulted area of the photosphere) was measured at mid-transit compared with a mean pre/post transit TSI of ~ 1365.9 W m^-2. These observations serve as a surrogate to future photometric observations of ETPs such as Kepler will deliver. Detailed analysis of the ToV, a rare event within our own solar system, with time-resolved radiometry augmented with high-resolution imagery provides a useful analogue for investigating the detectability and characterization of ETPs from observations that are anticipated in the near future. \\ ( http://arXiv.org/abs/astro-ph/0512251 , 988kb) -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
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Jan 10 2006, 03:51 PM
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#3
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Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Astrophysics, abstract
astro-ph/0601186 From: Gyula Szabo [view email] Date: Mon, 9 Jan 2006 16:10:04 GMT (132kb) Possibility of a photometric detection of "exomoons" Authors: Gy. M. Szabo, K. Szatmary, Zs. Diveki, A. Simon Comments: 5 pages, 4 figures, accepted by Astronomy and Astrophysics We examined which exo-systems contain moons that may be detected in transit. We numerically modeled transit light curves of Earth-like and giant planets that cointain moons with 0.005--0.4 Earth-mass. The orbital parameters were randomly selected, but the entire system fulfilled Hill-stability. We conclude that the timing effect is caused by two scenarios: the motion of the planet and the moon around the barycenter. Which one dominates depends on the parameters of the system. Already planned missions (Kepler, COROT) may be able to detect the moon in transiting extrasolar Earth-Moon-like systems with a 20% probability. From our sample of 500 free-designed systems, 8 could be detected with the photometric accuracy of 0.1 mmag and a 1 minute sampling, and one contains a stony planet. With ten times better accuracy, 51 detections are expected. All such systems orbit far from the central star, with the orbital periods at least 200 and 10 days for the planet and the moon, while they contain K- and M-dwarf stars. Finally we estimate that a few number of real detections can be expected by the end of the COROT and the Kepler missions. http://arxiv.org/abs/astro-ph/0601186 -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
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Jan 19 2006, 07:16 PM
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#4
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Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
Science/Astronomy:
* Close-Up on the Kepler Mission http://www.space.com/searchforlife/seti_kepler_060118.html The next transit of an Earth-sized planet will likely be observed in 2007 by the NASA Discovery Program's Kepler Mission. But the event won't happen in our solar system. * Asteroid Collision Fueled Ancient Dust Storm on Earth http://www.space.com/scienceastronomy/0601...eroid_dust.html One of the biggest cosmic dust storms of the past 80 million years left a blanket of material on Earth after an asteroid in space broke apart, researchers said today. -------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
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Mar 29 2006, 07:46 PM
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#5
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Member Group: Members Posts: 134 Joined: 13-March 05 Member No.: 191 |
According to the Kepler website, which doesn't look like it has been updated for a while, the Critical Design Review for Kepler was supposed to happen in February. Does anyone know if it happened, whether Kepler passed, and if it has enterred ATLO yet? We've heard second hand reports via Bruce that the budget has been busted, but that NASA will keep the money flowing. But has the project moved much lately?
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Mar 30 2006, 01:05 PM
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#6
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Junior Member Group: Members Posts: 23 Joined: 20-February 06 From: Poland, Wroclaw Member No.: 685 |
According to the Kepler website, which doesn't look like it has been updated for a while, the Critical Design Review for Kepler was supposed to happen in February. Does anyone know if it happened, whether Kepler passed, and if it has enterred ATLO yet? We've heard second hand reports via Bruce that the budget has been busted, but that NASA will keep the money flowing. But has the project moved much lately? I am interested in it as wellWell I downloaded the NASA's budget document and it seems that Kepler is going to be launched...unless I interpret the language in wrong way: http://www.nasa.gov/pdf/142458main_FY07_budget_full.pdf But the ATLO you speak about is written in the document as only to be conducted. I am really interested and hope somebody could share a light on this. |
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Guest_BruceMoomaw_* |
Mar 30 2006, 06:36 PM
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#7
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Guests |
Latest news is that the launch is currently set for mid-2008. They seem determined not to cancel it, although there may be further delays. (Once again, we have dramatic evidence of the extent to which Discovery proposers are tempted to understate their mission's cost and then try to persuade NASA to go along with it anyway. I hope Dawn hasn't set a disastrous precedent in this, or the Solar System Groupies may have shot themselves badly in the foot by demanding that it not be cancelled.)
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Mar 31 2006, 02:57 AM
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#8
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Member Group: Members Posts: 124 Joined: 23-March 06 Member No.: 723 |
Looks like a great mission,
we've got loads of exoplanet missions Corot, Kepler, TPF and Darwin ( If the budget stays good then NASA have some great exoplanet mission plans - unless of course NASA continues to hacking bits off TPF until there's nothing left ) |
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Apr 3 2006, 08:59 PM
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#9
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Member Group: Members Posts: 172 Joined: 17-March 06 Member No.: 709 |
According to the Kepler website, which doesn't look like it has been updated for a while, the Critical Design Review for Kepler was supposed to happen in February. Does anyone know if it happened, whether Kepler passed, and if it has enterred ATLO yet? But has the project moved much lately? Today, I noticed that the Kepler web site schedule has been updated. Launch has been slipped by 4 months due to fiscal matters, and is now scheduled for October 2008. In addition, the Critical Design Review is scheduled for this month, April 2006. In addition, Kepler will now feature a fixed High Gain antenna, instead of featuring a gimbal. According to the website, this was done to reduce risk, cost and complexity. However, this means that Kepler will miss 1 day's worth of observing per month. |
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May 22 2006, 03:05 AM
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#10
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Member Group: Members Posts: 172 Joined: 17-March 06 Member No.: 709 |
This is targeted at those with some familiarity with sources of Astronomical images. I am including links to the planned Field of View (FOV) for the Kepler mission. The first page links to a brief description of the FOV's location, while the second link is a more detailed pdf of the FOV itself. http://kepler.nasa.gov/sci/basis/fov.html http://kepler.nasa.gov/sci/basis/images/New_FOV_6m.pdf What I am looking for would be telescope images of the FOV, showing the star fields in some detail. I have searched the Kepler web site, but there are no such telescopic photos there. I think that is a shame. Kepler's mission involves searching for extra-solar planetary transits using a fancy photometer. The resulting light curves will be great to analyze, but the public (including me) will want to see just what Kepler was looking at. I think that a mosaic of images of the target FOV Milky Way star field should be magnificent. To me, such public outreach should be something that the Kepler team would want to pursue. Another Phil |
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May 22 2006, 09:58 AM
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#11
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Rover Driver Group: Members Posts: 1015 Joined: 4-March 04 Member No.: 47 |
Are there known transiting exoplanets in that piece of sky for cross-checking purposes?
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May 22 2006, 02:07 PM
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#12
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Member Group: Members Posts: 159 Joined: 4-March 06 Member No.: 694 |
Are there known transiting exoplanets in that piece of sky for cross-checking purposes? I know two exo-planets have been discovered by the use of the transit method. However, the only planet that could be used to calibrate or test such technologies at the current time is Venus. Scientists used the June 8, 2004 transit to test alot of devices and technologies that Kepler and future missions will use. The most important one was done by ACRIM which showed a orbiting spacecraft CAN detect a minute drop (about 0.1%) in a parent star's (the Sun!) light reaching a detector. Good news though: There will be another transit on June 6, 2012. I bet this will be used as well! -------------------- I call heaven and earth to witness against you this day, that I have set before thee life and death, the blessing and the curse; therefore choose life, that thou mayest live, thou and thy seed.
- Opening line from episode 13 of "Cosmos" |
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May 22 2006, 07:02 PM
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#13
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Member Group: Members Posts: 235 Joined: 2-August 05 Member No.: 451 |
The most important one was done by ACRIM which showed a orbiting spacecraft CAN detect a minute drop (about 0.1%) in a parent star's (the Sun!) light reaching a detector. Good news though: There will be another transit on June 6, 2012. I bet this will be used as well! It seems to me that many more opportunities happen than this. We need only look at the light curve of medium to large asteroids as the Earth, or Venus, or Mars, or Jupiter transit the Sun from their locations. There must be dozens of such events per year. More if you want to look at smaller objects. |
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Guest_BruceMoomaw_* |
May 23 2006, 01:59 AM
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#14
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Guests |
This is targeted at those with some familiarity with sources of Astronomical images. I am including links to the planned Field of View (FOV) for the Kepler mission. The first page links to a brief description of the FOV's location, while the second link is a more detailed pdf of the FOV itself. http://kepler.nasa.gov/sci/basis/fov.html http://kepler.nasa.gov/sci/basis/images/New_FOV_6m.pdf What I am looking for would be telescope images of the FOV, showing the star fields in some detail. I have searched the Kepler web site, but there are no such telescopic photos there. I think that is a shame. Kepler's mission involves searching for extra-solar planetary transits using a fancy photometer. The resulting light curves will be great to analyze, but the public (including me) will want to see just what Kepler was looking at. I think that a mosaic of images of the target FOV Milky Way star field should be magnificent. To me, such public outreach should be something that the Kepler team would want to pursue. Another Phil I believe that they do intend to get a lot of data on star variability as a fringe benefit from the Kepler mission -- just as ESA's cancelled Eddington mission would have done the same two things, but in reverse order of priority. By the way, one selling point for the proposed "Joint Dark Energy Mission" that NASA and the Dept. of Energy were planning to team up on as the first "Beyond Einstein" mission -- although those have been put on indefinite hold due to the serious funding problems in NASA's Astrophysics Division -- was that, by adding just $100 million to its total cost, it could follow up its initial measurements of very distant supernovas with a very extensive microlensing census of planets in one of the Magellanic Clouds. |
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May 23 2006, 03:57 AM
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#15
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Member Group: Members Posts: 172 Joined: 17-March 06 Member No.: 709 |
Here is a direct look at Kepler's FOV (Field of View). Kepler will be staring at this FOV for 4 years, looking for transits. In this FOV, there are about 200,000 stars, half of which will meet the criteria for planetary search (single, non-variable, etc.). Therefore, Kepler will be sorting through the brightness stability of about 100,000 stars. I think that it would add immensely to one's appreciation of the magnitude of Kepler's mission if there were actual images of the galactic star fields inserted into the FOV above. In fact, it would be helpful to have high-res digital images of each of the 21 sub-fields (each of these sub-fields will be covered by one of Kepler's CCD's). Does anyone have access to a good source of Milky Way digital imagery, especially of the area near Cygnus, shown above? Another Phil
Attached File(s)
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May 23 2006, 03:10 PM
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#16
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Senior Member Group: Members Posts: 2454 Joined: 8-July 05 From: NGC 5907 Member No.: 430 |
-------------------- "After having some business dealings with men, I am occasionally chagrined,
and feel as if I had done some wrong, and it is hard to forget the ugly circumstance. I see that such intercourse long continued would make one thoroughly prosaic, hard, and coarse. But the longest intercourse with Nature, though in her rudest moods, does not thus harden and make coarse. A hard, sensible man whom we liken to a rock is indeed much harder than a rock. From hard, coarse, insensible men with whom I have no sympathy, I go to commune with the rocks, whose hearts are comparatively soft." - Henry David Thoreau, November 15, 1853 |
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Jul 1 2006, 03:42 AM
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#17
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Member Group: Members Posts: 172 Joined: 17-March 06 Member No.: 709 |
Here is an image of a Milky Way star field in the vicinity of Alpha Cygni (Deneb). http://video.library.gatech.edu/Barnard_Pr...t1-pl045_sm.jpg This image is near the Kepler FOV and gives an idea of the task facing Kepler. Recall that Kepler will be staring at a star field, containing about 100,000 - 200,000 stars, for 4 years looking for planetary transits. This image is part of an on-line collection of classic Milky Way images obtained by E.E. Barnard. The search page can be found at http://video.library.gatech.edu/cgi-bin/bp...rch.pl?search=0 Another Phil |
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Guest_AlexBlackwell_* |
Feb 7 2007, 04:49 PM
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#18
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Guests |
The Kepler Mission: The Search for Earth-like Planets
By Leonard David Senior Space Writer, Space.com posted: 07 February 2007 06:27 am ET |
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Jul 16 2007, 03:18 PM
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#19
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
-------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Jul 16 2007, 03:26 PM
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#20
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Founder Group: Chairman Posts: 14434 Joined: 8-February 04 Member No.: 1 |
"There's a new team in town and we don't work that way"
I think we should club together and buy Alan a sherif badge All credit to the guy - these are not easy decisions to make - and the best decision is rarely the easiest one. Doug |
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Jul 16 2007, 03:26 PM
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#21
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
I really love the Kepler mission concept, and I've been sad to see it delayed so long, but (reading the article) it sure sounds like Alan was spot-on with this one. Sadly, it feeds my perception that most of Nasa's problems are self-inflicted. On the bright side, it suggests things could get much better if Alan keeps making calls like this.
--Greg |
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Jul 16 2007, 03:45 PM
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#22
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
I think we should club together and buy Alan a sherif badge ... -------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Jul 16 2007, 05:08 PM
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#23
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Member Group: Members Posts: 321 Joined: 6-April 06 From: Cape Canaveral Member No.: 734 |
"There's a new team in town and we don't work that way" I think we should club together and buy Alan a sherif badge All credit to the guy - these are not easy decisions to make - and the best decision is rarely the easiest one. Doug Why this so different from the first Dawn decision? |
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Jul 17 2007, 12:33 PM
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#24
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Director of Galilean Photography Group: Members Posts: 896 Joined: 15-July 04 From: Austin, TX Member No.: 93 |
Too bad Alan wasn't around to prevent the GP-B fiasco.
Slightly related...We've often heard the quote, "That sure would look great in the Smithsonian". Got two questions: 1. Are there any projects that were killed and placed in the Smithsonian, or A&S museums in general? 2. Really, wouldn't you be disappointed to see an unlaunched space probe sitting there in the A&S museum? I think it would be better to mount it in the foyer of the managing team's facility as a reminder. -------------------- Space Enthusiast Richard Hendricks
-- "The engineers, as usual, made a tremendous fuss. Again as usual, they did the job in half the time they had dismissed as being absolutely impossible." --Rescue Party, Arthur C Clarke Mother Nature is the final inspector of all quality. |
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Jul 17 2007, 12:51 PM
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#25
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Founder Group: Chairman Posts: 14434 Joined: 8-February 04 Member No.: 1 |
1. Are there any projects that were killed and placed in the Smithsonian, or A&S museums in general? Two examples - one big, one small. The Saturn V at JSC is built from parts destined for Apollo 18/19 and/or the third stage that got pulled off to make room for Skylab. And Marie Curie - the Sojourner spare - then destined for the 01 lander, which got cancelled, and never made it onto the Phoenix payload - not sure where she lives now but she's been to exhibitions afaik. Doug |
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Jul 17 2007, 03:18 PM
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#26
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Member Group: Members Posts: 321 Joined: 6-April 06 From: Cape Canaveral Member No.: 734 |
Back up Skylab,
Agena Triana is some where AFP-888, P80-1, Teal Ruby |
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Jul 18 2007, 06:12 AM
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#27
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Senior Member Group: Members Posts: 1870 Joined: 20-February 05 Member No.: 174 |
"...The Saturn V at JSC is built from parts destined for Apollo 18/19 and/or the third stage that got pulled off to make room for Skylab..."
I believe there are 3 Saturn 5's on display, the third one at Marshall or somewhere Huntsville, though only 2 flight vehicles remained after Apollo's 18 and 19 were budget canceled. The third vehicle is the dummy pad-checkout vehicle that was used to test VAB/Crawler/Pad operations and connections/hookups before Apollo 4's Saturn 501 was prepared for launch. I read somewhere that parts of it are included in both the Canaveral and Houston display vehicles, so none of the vehicles on display is 100% flight capable hardware. |
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Jul 18 2007, 11:26 AM
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#28
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Founder Group: Chairman Posts: 14434 Joined: 8-February 04 Member No.: 1 |
This is what Wiki says:
Currently there are three Saturn Vs on display, all displayed horizontally: A Saturn V on display at the U.S. Space & Rocket Center in Huntsville, Alabama. A Saturn V on display at the U.S. Space & Rocket Center in Huntsville, Alabama. * At the Johnson Space Center made up of first stage of SA-514, the second stage from SA-515 and the third stage from SA-513. * At the Kennedy Space Center made up of S-IC-T (test stage) and the second and third stages from SA-514. * At the U.S. Space & Rocket Center, made up of S-IC-D, S-II-F/D and S-IVB-D (all test stages not meant for actual flight)(soon to be moved to a new visitor's center). So the JSC one is all flight hardware (and the only one to be so) - just not from the same vehicle. |
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Jul 18 2007, 03:46 PM
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#29
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Senior Member Group: Members Posts: 1591 Joined: 14-October 05 From: Vermont Member No.: 530 |
The space station appears destined to contribute a lot of hardware to these lists.
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Jul 18 2007, 08:10 PM
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#30
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Member Group: Members Posts: 321 Joined: 6-April 06 From: Cape Canaveral Member No.: 734 |
Only 3 MPLM's
the rest wasn't built |
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Guest_PhilCo126_* |
Aug 31 2007, 06:46 PM
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#31
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Guests |
In which parts of the Electromagnetic spectrum are Kepler's detectors active ( Visible and Infrared ? )
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Guest_AlexBlackwell_* |
Aug 31 2007, 06:56 PM
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#32
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Guests |
In which parts of the Electromagnetic spectrum are Kepler's detectors active ( Visible and Infrared ? ) From the Kepler website: "The [photometer] has a spectral bandpass from 400 nm to 850 nm." |
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Guest_PhilCo126_* |
Sep 8 2007, 01:05 PM
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#33
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Guests |
Kepler mission: Work in progress
http://www.ballaerospace.com/gallery/kepler/ |
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May 5 2008, 06:51 PM
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#34
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Member Group: Members Posts: 213 Joined: 21-January 07 From: Wigan, England Member No.: 1638 |
-------------------- "I got a call from NASA Headquarters wanting a color picture of Venus. I said, “What color would you like it?” - Laurance R. Doyle, former JPL image processing guy
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Jun 14 2008, 04:12 PM
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#35
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Member Group: Members Posts: 124 Joined: 23-March 06 Member No.: 723 |
Kepler will be staring at this FOV for 4 years, looking for transits. In this FOV, there are about 200,000 stars, half of which will meet the criteria for planetary search (single, non-variable, etc.). Kepler is expected to be able to discover at least 50 earth sized planets |
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Sep 27 2008, 06:27 PM
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#36
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
Another Kepler update.
http://www.jpl.nasa.gov/news/news.cfm?release=2008-179 The spacecraft is in Colorado and survived the termal vacuum test. I note they're only saying it'll launch in 2009 -- I wonder if they have quietly backed off the April 2009 date. Anyway, NASA elsewhere still shows an April 10 launch date. http://www.nasa.gov/missions/highlights/schedule.html --Greg |
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Oct 8 2008, 05:04 PM
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#37
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
They're now showing Kepler scheduled for launch: 2009 March 4, 10:46 pm EST on the Kepler web site.
http://www.kepler.arc.nasa.gov/ Still no countdown though. :-) --Greg |
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Oct 11 2008, 08:04 PM
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#38
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Member Group: Members Posts: 205 Joined: 14-April 06 From: Seattle, WA Member No.: 745 |
The NASA Launch Schedule now has the Kepler launch set for April 10.
http://www.nasa.gov/missions/highlights/schedule.html |
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Oct 15 2008, 04:06 PM
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#39
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Member Group: Members Posts: 205 Joined: 14-April 06 From: Seattle, WA Member No.: 745 |
Yesterday, NASA moved the launch of Kepler back to "no earlier than" March 5. They do not list a launch time.
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Feb 21 2009, 07:56 PM
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#40
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Member Group: Members Posts: 183 Joined: 22-October 05 From: Cape Canaveral, FL Member No.: 534 |
I haven't seen any posts on Kepler in a while and with the launch less than two weeks off I figured I might post :-)
The Kepler observatory made the 20 mile trip from the Astrotech cleanroom to LC-17B Thursday morning and after a couple days of delay due to weather was this morning lifted and mounted atop the 13-story Delta 2 rocket that will take it into space in 12 days. Some cleanroom shots from the media viewing a few weeks ago. Launch is on target for Thursday March 5 at 10:48pm EST. There will be two launch windows of exactly three minutes each that day, stretching from 10:48:43 - 10:51:43pm and 11:16:34 - 11:19:34pm EST. NASA TV coverage begins at about 8pm or 8:30pm; www.nasa.gov/ntv. -------------------- |
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Feb 22 2009, 01:11 AM
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#41
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Dublin Correspondent Group: Admin Posts: 1799 Joined: 28-March 05 From: Celbridge, Ireland Member No.: 220 |
Thanks for the update Ben - much appreciated.
Slightly OT but I'm curious about how much time you have to spend just hanging about waiting for launches to get windows defined with a confidence level that enables you to get all your kit prepared for setting up - basically do you end up having to sacrifice weeks\months of time in order to be sure of getting a shot or are you able to actually work a more or less normal life around launch windows? |
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Feb 26 2009, 06:44 PM
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#42
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Junior Member Group: Members Posts: 68 Joined: 10-September 05 Member No.: 493 |
I hope that Kepler would have to wait for the results is less than Corot.
http://www.kepler.arc.nasa.gov/pdf_files/3...2-19_smfile.pdf -------------------- |
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Feb 26 2009, 07:03 PM
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#43
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The Poet Dude Group: Moderator Posts: 5551 Joined: 15-March 04 From: Kendal, Cumbria, UK Member No.: 60 |
Thanks for the link to the Kepler info Byran, fascinating stuff, but there's not a lot of point copying a great chunk of it - or other reports, etc - into your post too. Best to let people follow the link and read it for themselves if they want to.
-------------------- |
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Feb 26 2009, 11:11 PM
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#44
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
Although I think this bit is worth posting, since it answers the question of "how long must we wait for results?"
"The first planets discovered by Kepler will be gas giants, similar in size to Jupiter, in close orbits lasting only a few days around their parent stars. Planets in Mercury-like orbits with orbital periods of only a few months will be discovered using data from the first year of operations. Finding Earth-size planets in Earth-like orbits will require the entire length of the 3.5-year Kepler Mission." If I recall correctly, the reason it takes as long as it does is that they need to see the planet transit three times; once to discover it, a second time to get the period, and the third time to confirm the result. --Greg |
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Feb 27 2009, 07:28 PM
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#45
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Junior Member Group: Members Posts: 89 Joined: 27-August 05 From: Eccentric Mars orbit Member No.: 477 |
Launch has been pushed back a day to check the Delta II for any common parts with the Taurus that failed this week. Launch now no earlier than Friday, 6 Mar 2009 at 10:49:57 p.m. EST (Saturday 7 Mar 2009 03:49:57 UTC)
http://spaceflightnow.com/delta/d339/status.html |
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Mar 3 2009, 12:52 AM
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#46
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Member Group: Members Posts: 183 Joined: 22-October 05 From: Cape Canaveral, FL Member No.: 534 |
The Delta 2 rocket with Kepler has been cleared for blastoff Friday night at 10:49pm. There is a 90% chance of acceptable weather conditions predicted.
http://spaceflightnow.com/delta/d339/status.html -------------------- |
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Mar 3 2009, 08:59 PM
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#47
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Member Group: Members Posts: 646 Joined: 23-December 05 From: Forest of Dean Member No.: 617 |
*ulp*. This is the most nervous I'm going to be until the MSL launch / EDL. (Of couse, with Kepler the launch is "easy" bit... )
-------------------- --
Viva software libre! |
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Mar 4 2009, 09:57 AM
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#48
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
imipak, Kepler and its possibilites is definitily a mission that fits in my "special cookie" condition...what will it find? What surprises expect us? A legion of earth-like planets or the absence of these? Either way it will have a huge impact in the future not only in space exploration but mostly, in my opinion, in our perspective towards the place we occupy in the universe. It will, surely, open our eyes and pave the way to a different reality. Truly a revolutionary mission for a species like ours...therefore here I am, with this strange, good feeling in the stomach, all excited, all nervous and crossing my fingers. Probably the launch I am following with more anticipation...Friday will be a great day...
-------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Mar 4 2009, 08:01 PM
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#49
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Member Group: Members Posts: 646 Joined: 23-December 05 From: Forest of Dean Member No.: 617 |
I hope, _hope_, /HOPE!/ that you're right. Until Kepler's safely in orbit without mishap, though, I can't think of those as anything but potential possibilities. I'm a devout rationalist, but events like this really help me understand why, and how, superstitions develop. Pucker factor: 0.4...
I'm trying to persuade a colleague at work with a latent interest in UMSF to wake his kids up to watch the launch. He expresses what he thinks is a rational aversion to spending money on U?MSF in general, but I can tell he secretly digs the "cool" factor. I'm guessing his kids are his weak point! -------------------- --
Viva software libre! |
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Mar 4 2009, 08:09 PM
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#50
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
And how cool can it get the fact of watching the launch of a mission that has the potential to change the way we see the Universe?
I would like to tell my grandchildren that I was there watching the launch of Kepler, the one who first sighted a-n-o-t-h-e-r earth, but hey...we're all talking about in the hypothetical field here...man...why does friday take so long to arrive? -------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Mar 4 2009, 08:53 PM
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#51
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Member Group: Members Posts: 646 Joined: 23-December 05 From: Forest of Dean Member No.: 617 |
I'm sure there's a Portuguese equivalent of the English expression: "A watched pot never boils" ... *grin*
-------------------- --
Viva software libre! |
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Mar 4 2009, 09:30 PM
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#52
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
Yes, I know the expression...I have chosen another one for the occasion...
Barco parado não faz viagem. Tictactictactictac.... -------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Guest_PhilCo126_* |
Mar 5 2009, 08:42 AM
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#53
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Guests |
Did anyone found a weblink with the dimensions of the 1040 kilograms Kepler Space Observatory?
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Mar 5 2009, 11:18 AM
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#54
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
Nope...I would say 5 to 6 meters tall...
Only found the info at the mission site, with the photometer dimensions it is just a question of doing the maths... http://kepler.nasa.gov/sci/design/spacecraft.html BTW, Beyond the Cradle, spacEurope's sucessor, is welcoming some members of the Kepler team, the last one was Alan Gould, here's a bit of it, revealing how this guys imagination is running wild...gotta love science... : "We just finished 2 days of very exciting Kepler Science Team meetings here in Cocoa Beach FL (Mon-Tue, Mar 2-3), getting ready for Friday’s launch. We’re all extremely suspenseful, elated, and hopeful all at the same time. The science discussions were fascinating and intriguing–some about all the different types of transits we might observe with different classes of stars, different sizes of planets, shapes and periods of orbits, planets orbiting eclipsing binary stars, all stimulating thoughts of strange and wonderful new worlds." If you scroll down you will also find a piece by Edna DeVore...everything that helps passing the time is welcome... -------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Guest_PhilCo126_* |
Mar 5 2009, 03:21 PM
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#55
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Guests |
Ben Cooper Launchphotography has amazing photos of the Kepler Space Observatory:
http://www.launchphotography.com/Kepler_cleanroom.html for spacecraft dimensions: google --> Kepler Press Kit |
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Mar 5 2009, 04:59 PM
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#56
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
I have a "no peanuts" rule this time, though . . .
--Greg :-) |
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Mar 5 2009, 05:25 PM
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#57
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
If my time zone doesn't fail me there will be within 30 minutes (1 p.m. EST) a Kepler Mission Pre-Launch Science Briefing at NASATV.
EDITED: Speaking of hours help me here (it's always the same thing with every event...), the launch will take place in my GMT time on Saturday 03:49:57AM? Correct? Or not?... EDITED: Stu just made me a very happy man... http://countdown.ksc.nasa.gov/elv/ -------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Mar 6 2009, 11:33 AM
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#58
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Member Group: Members Posts: 202 Joined: 9-September 08 Member No.: 4334 |
16 hours left...
fingers crossed... |
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Mar 6 2009, 12:02 PM
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#59
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Senior Member Group: Members Posts: 3648 Joined: 1-October 05 From: Croatia Member No.: 523 |
-------------------- |
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Mar 6 2009, 12:42 PM
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#60
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
Great to see the attention it is getting on CNN's website...top story!
-------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Mar 6 2009, 02:43 PM
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#61
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Member Group: Members Posts: 279 Joined: 19-August 07 Member No.: 3299 |
I am trying to find out about the future position of Kepler with respect to Earth. So far I have found the following info which does not satisfy me since it does not tell me about how far will be Kelper following up to Earth with a constant distance?
QUOTE Sixty-two minutes after launch, Kepler will have separated entirely from its rocket and will be in its final Earth-trailing orbit around the sun, an orbit similar to that of NASA's Spitzer Space Telescope. |
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Mar 6 2009, 02:56 PM
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#62
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Rover Driver Group: Members Posts: 1015 Joined: 4-March 04 Member No.: 47 |
My impression was that it would move further and further away from Earth.
Google is very useful: http://redorbit.com/images/gallery/kepler/...3/41/index.html |
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Mar 6 2009, 03:40 PM
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#63
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Member Group: Members Posts: 237 Joined: 22-December 07 From: Alice Springs, N.T. Australia Member No.: 3989 |
future position of Kepler with respect to Earth. I went here http://kepler.nasa.gov/sci/design/orbit.html NASA press kit is interesting - orbit info on page 14 http://www.nasa.gov/pdf/314125main_Kepler_...2-19_smfile.pdf Kepler needs uninterrupted viewing to ensure most efficient use of observation time for planetary transits ("100,000 stars will be monitored continuously and simultaneously")!!!!! - therefore it is being put into a heliocentric orbit that trails behind the earth where earth/moon will not block the view. Also important - being further away from effects of things like earth/moon gravity, magnetoshpere etc means good stability and so better pics. Kepler's orbit will gradually fall further behind the Earth (worst case 0.5 AU after 4 years) but it will still be within communications range even after the end of the nominal mission - 3.5 years. Will probably get funding a bit longer after that. Hope this helps. |
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Mar 6 2009, 05:18 PM
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#64
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Member Group: Members Posts: 279 Joined: 19-August 07 Member No.: 3299 |
Thank you HughFromAlice. Its heliocentric orbit takes 371 days means that it will be keeping away from Earth in every year until it will meet again with Earth in very far future.
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Mar 6 2009, 11:10 PM
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#65
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
Man...Jon Jenkins back at BTC contagiated me with is emotions...if I was intending to stay calm I can't avoid to become all emotional...
"I’ve been waiting for this moment for 14 years. Tonight, NASA Discovery Program’s Kepler Mission will blast off at 10:48 pm from Canaveral Air Force Station taking the hopes and dreams of myself and so many other people who’ve worked so hard for so long to make this moment happen. It feels like I’m on a roller coaster on its way up to the first big hill, ka-ching, ka-ching. I can just start to see the big drop just beyond the crest of the tracks, and at launch there will be no turning back and we’ll be taken along for one of the most thrilling rides of our lives. Yesterday I watched “Magnificent Desolation” at the IMAX theater at KSC Visitor Complex. Unbidden tears formed in my eyes and flowed down my cheeks towards the end of the film. The enormity of the goals and aspirations achieved by the Apollo Program are overwhelming." -------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Mar 7 2009, 12:26 AM
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#66
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Merciless Robot Group: Admin Posts: 8785 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Great, moving words. I think all of us are pretty excited, but I can only imagine how the team members feel right now.
GO KEPLER!!!!! -------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Guest_Zvezdichko_* |
Mar 7 2009, 06:07 AM
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#67
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Guests |
Looks like launch was successful.
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Mar 7 2009, 07:26 AM
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#68
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Member Group: Members Posts: 399 Joined: 28-August 07 From: San Francisco Member No.: 3511 |
Brilliant launch Kepler, (I'm Ecstatic)
Go Find 'Em Flea on the Headlight! -------------------- 'She drove until the wheels fell off...'
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Guest_PhilCo126_* |
Mar 7 2009, 07:59 AM
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#69
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Guests |
Indeed, together with CoRoT a very interesting mission to look forward to...
BIS Spaceflight May 2009 will have an article on Kepler |
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Mar 7 2009, 01:24 PM
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#70
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The Poet Dude Group: Moderator Posts: 5551 Joined: 15-March 04 From: Kendal, Cumbria, UK Member No.: 60 |
Gorgeous launch pics by Ben Cooper...
http://www.launchphotography.com/Kepler.html Second one is an absolute beauty, Ben, well done! -------------------- |
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Mar 7 2009, 01:24 PM
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#71
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Newbie Group: Members Posts: 1 Joined: 6-March 09 Member No.: 4631 |
I don't know about Corot... It seems it didn't gone so well with planets detections There is a new article here: http://www.cnes.fr/web/CNES-fr/7492-jour-de-chance.php
I tried to translate it with google and I am pretty disapointed: To date, 7 CoRoT exoplanet discovered with certainty, including the smallest ever detected. This is an array of hunting already significant, but it is actually far less than what the researchers expected to discover. "We are half the planets as we had hoped" said Peter Barge. "We were so intrigued that we first thought there was a problem in detection methods. We distributed to all teams of the light curves with simulated transits to see if it was the methods of signal processing that were reviewed. But all the simulated planets had been identified ... " Another hypothesis, that of a noise, a disturbance signal which would be higher for low-light stars, often longer. "We will soon be able to better filter the residual instrumental noise on the low stars. We will see then if we find the planets expected. » " But if no new planet revealed the tip of the eclipse, it should be made to face the facts: the problem will not come from the instrument, but the stars themselves. "Maybe the planets are formed preferentially in our little galaxy" advance Pierre Barge with a smile. "Maybe the planets are formed preferentially in our little galaxy" advance Pierre Barge with a smile. The Sun and its retinue of planets and that a majority of the exoplanets detected are located in one arm of the galaxy, the Orion arm, a fairly dense area that could be more conducive to the formation of planets and other regions. But for now, this is still a hypothesis, "says the researcher. |
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Mar 7 2009, 01:57 PM
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#72
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Member Group: Members Posts: 340 Joined: 11-April 08 From: Sydney, Australia Member No.: 4093 |
Does anybody know where I can find the spice kernels for Kepler? Since it's orbiting the Sun, I would want to include it on my site.
since it does not tell me about how far will be Kelper following up to Earth with a constant distance? It will slowly fall behind Earth as it goes around the Sun ... Kepler orbits the Sun and not Earth. To keep it at a constant distance from Earth would involve at least two major trajectory correction maneuvers, so it is much more efficient to launch it into an orbit which is similar to that of Earth -------------------- |
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Mar 7 2009, 03:19 PM
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#73
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Member Group: Members Posts: 279 Joined: 19-August 07 Member No.: 3299 |
I am glad to know that the launch of Kepler was stunning and succesfull in spite of the fact that there were minor problems with some delay of relaying data to space center.
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Mar 7 2009, 07:45 PM
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#74
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Newbie Group: Members Posts: 17 Joined: 5-January 06 Member No.: 636 |
Congratulations on a succesful launch to everyone involved with the Kepler mission.
I have two questions which someone here may be able to enlighten me on: 1. Why wasn't an L2 orbit used (similar to the forthcoming Herschel and Planck missions)? Wouldn't an L2 orbit give a longer mission lifetime? 2. If/when an exo-planet is detected, is there any way to determine the eccentricity of it's orbit (either by Kepler or by ground based observations)? Best regards, Brian |
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Mar 7 2009, 08:28 PM
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#75
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Senior Member Group: Members Posts: 1669 Joined: 5-March 05 From: Boulder, CO Member No.: 184 |
Yes, the radial velocity method can determine the eccentricity...
-------------------- Steve [ my home page and planetary maps page ]
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Mar 7 2009, 09:28 PM
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#76
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Member Group: Members Posts: 813 Joined: 29-December 05 From: NE Oh, USA Member No.: 627 |
Congratulations to the mission launch team on this beautiful launch. Heart was in my mouth waiting for confirmation of Goldstone signal. In 1991, when the pulsar planets were announced, we started writing the Book of ExoWorlds. How many pages will be added in 4 years time? KEPLER (and COROT) will answer a question I have been wanting an answer to ever since I was old enough to understand the question. How common are Earth sized planets? As Alan Boss has noted, we are entering the platinum age of explanetary science. Craig |
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Mar 7 2009, 09:56 PM
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#77
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Newbie Group: Members Posts: 17 Joined: 5-January 06 Member No.: 636 |
Yes, the radial velocity method can determine the eccentricity... Using spectroscopy/doppler shift measurements? That's possible for Earth-sized planets? Even if there's a Jupiter-sized planet in the same system(messing things up)? Wow. I think I'll have to try to crunch some numbers on that, to get my head around it. The more I think about it, the more amazing the process of making those measurements, and disentangling them, becomes. Thanks. |
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Mar 8 2009, 01:49 AM
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#78
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Member Group: Members Posts: 213 Joined: 21-January 07 From: Wigan, England Member No.: 1638 |
1. Why wasn't an L2 orbit used (similar to the forthcoming Herschel and Planck missions)? Wouldn't an L2 orbit give a longer mission lifetime? I recall L2 being mentioned early on, but they descoped along the way in order to fit on a Delta II -- it's sobering to think Kepler was rejected four times before being accepted! |
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Mar 8 2009, 02:59 AM
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#79
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Forum Contributor Group: Members Posts: 1374 Joined: 8-February 04 From: North East Florida, USA. Member No.: 11 |
We saw the launch last night in real life from our location in Orange Park, FL. The Delta 2 looked like a large firework rocket at first. Then an orange light which noticeably accelerated. We have seen the Shuttle launch several times and also I think one of the Rovers.
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Mar 8 2009, 03:34 AM
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#80
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Member Group: Members Posts: 903 Joined: 30-January 05 Member No.: 162 |
It would not be confirmable by the 3 observation criteria, but it would still be interesting to review Kepler light curve data for brightenings possibly due to equivalents of Kreutz sun grazers. (IIRC, some Kreutz sun grazers have been visually observed in daytime near the sun, implying a summed magnitude increase greater than the expected decrease in magnitude due to a planetary type stellar transit)
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Mar 8 2009, 06:24 AM
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#81
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Merciless Robot Group: Admin Posts: 8785 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Considering that the Kreutz group is thought to have originated from the breakup of a single large object perhaps less than a thousand years ago, and that a comet's peak brightness during periastron lasts only a few days at most, I think detection of such events by Kepler are statistically unlikely in the extreme.
-------------------- A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Mar 8 2009, 03:06 PM
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#82
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Senior Member Group: Members Posts: 1669 Joined: 5-March 05 From: Boulder, CO Member No.: 184 |
Using spectroscopy/doppler shift measurements? That's possible for Earth-sized planets? Even if there's a Jupiter-sized planet in the same system(messing things up)? Wow. I think I'll have to try to crunch some numbers on that, to get my head around it. The more I think about it, the more amazing the process of making those measurements, and disentangling them, becomes. Thanks. Well I should qualify that the radial velocity method generally works for planets larger than the Earth, depending on how close they are to their parent star. I've heard radial velocity limits between .3 and 3 m/s that would depend on the brightnesss of the parent star. http://kepler.nasa.gov/sci/capabilities.html It can determine the eccentricity though as well as work with multiple planets to disentangle the individual signals. -------------------- Steve [ my home page and planetary maps page ]
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Mar 8 2009, 03:10 PM
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#83
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Senior Member Group: Members Posts: 1669 Joined: 5-March 05 From: Boulder, CO Member No.: 184 |
It seems to me that many more opportunities happen than this. We need only look at the light curve of medium to large asteroids as the Earth, or Venus, or Mars, or Jupiter transit the Sun from their locations. There must be dozens of such events per year. More if you want to look at smaller objects. Perhaps though the light curves of the asteroids would be more influenced by their rotation compared with a star? -------------------- Steve [ my home page and planetary maps page ]
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Mar 8 2009, 04:11 PM
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#84
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Senior Member Group: Members Posts: 2922 Joined: 14-February 06 From: Very close to the Pyrénées Mountains (France) Member No.: 682 |
We saw the launch last night in real life from our location in Orange Park, FL. The Delta 2 looked like a large firework rocket at first. Then an orange light which noticeably accelerated. We have seen the Shuttle launch several times and also I think one of the Rovers. Opportunity was launched at night. An watch out next wednesday you'll enjoy Discovery's night launch too. Lucky man. -------------------- |
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Mar 8 2009, 06:11 PM
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#85
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Newbie Group: Members Posts: 17 Joined: 5-January 06 Member No.: 636 |
I recall L2 being mentioned early on, but they descoped along the way in order to fit on a Delta II -- it's sobering to think Kepler was rejected four times before being accepted! Thanks Del. I'm certainly glad Kepler made the cut in the end!Some back-of-the-envelope calculations tell me that Kepler has a max. dV of ~23m/s (assuming 12kg propellant, ISP 2000Ns/kg) From what I can find out on the web, Herschel(direct injection to L2 halo orbit) will need ~200m/s dV (inc. safety margin). So Kepler would require ~90kg of extra propellant on board to match that. The largest component of the Herschel dV budget seems to be for correction of launcher error. So I guess it's largely down to the accuracy required for a launch to L2 halo orbit (compared to a launch to Earth-trailing heliocentric orbit). @scalbers: Thanks so much for the link to the Kepler/Planet Detection Methods page. That makes the limitations of the different methods quite clear. I was just wondering if a system similar to the Earth/Sun were detected, could we tell whether it was a "habitable" place (low eccentricity) or being alternately roasted and frozen every orbit (high eccentricity). Best regards, Brian |
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Mar 8 2009, 07:53 PM
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#86
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Member Group: Members Posts: 723 Joined: 13-June 04 Member No.: 82 |
That makes the limitations of the different methods quite clear. I was just wondering if a system similar to the Earth/Sun were detected, could we tell whether it was a "habitable" place (low eccentricity) or being alternately roasted and frozen every orbit (high eccentricity). It would be possible to determine that a particular planet had a high-eccentricity orbit using only transit information (under certain viewing circumstances), but many high-eccentricity planets would not be recognized as such. The time between successive planetary transits (combined with the primary star's estimated mass) determines the semi-major axis, while the total duration of the transit from first to last contact is determined by the "impact factor" (how central the transit is, relative to the stellar disk), the diameter of the stellar primary and the velocity of the planet while transiting in front of the star. So if the stellar parameters are reasonably well-known, a transit duration longer than that expected from a central transit of a low-eccentricity planet says that the planet must be slower (and hence farther from its primary) at that moment than expected at any time in a low-eccentricity orbit, and so its eccentricity must be high. However, a transit duration less than the expected duration of a central transit and a low-eccentricity orbit means little, since the transit might be off-center or grazing, which would reduce its duration as well. |
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Mar 8 2009, 08:00 PM
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#87
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Member Group: Members Posts: 131 Joined: 31-May 08 From: San Carlos, California, USA Member No.: 4168 |
I made it out to the Kepler launch party here at NASA Ames in Mountain View, CA. After the launch, masses of people starting filing out and I was able to grab a few minutes with Dr. Tom Roellig, co-investigator for Kepler. There were a few of us pelting him with questions, some of them interesting.
- "Flea on a headlight" whatever, what's the intensity resolution? Kepler has 16-bit A2Ds. - Kepler has an 90 megapixel digital camera. Is all that data beamed back to Earth? No, just the pixels that have a star sitting on them, about 5%. Then compression is about 2:1. - Does a star move from pixel to pixel during measurements? No. A star will sit within one pixel with a LARGE amount of the pixel to spare. - What if a star just happens to be right on the border of one pixel and another pixel? Kepler blurs adjacent pixels to account for this. (Not clear to me if this is accomplished in software or hardware.) - Why is Kepler's life span just six years? Not enough fuel. Have to desaturate from time to time, no choice. - (My question) Can we expect preliminary data to be published in May or June? Yes and no. The Kepler team will have some data and preliminary "subjects of interest" but they won't publish it. Because some media will misrepresent the data and you'll have headlines such as "30 Earths found!!!" and NASA will look bad for no reason when NASA has to clean up the mess. |
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Mar 8 2009, 08:53 PM
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#88
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Senior Member Group: Members Posts: 1669 Joined: 5-March 05 From: Boulder, CO Member No.: 184 |
It would be possible to determine that a particular planet had a high-eccentricity orbit using only transit information (under certain viewing circumstances), but many high-eccentricity planets would not be recognized as such. The time between successive planetary transits (combined with the primary star's estimated mass) determines the semi-major axis, while the total duration of the transit from first to last contact is determined by the "impact factor" (how central the transit is, relative to the stellar disk), the diameter of the stellar primary and the velocity of the planet while transiting in front of the star. So if the stellar parameters are reasonably well-known, a transit duration longer than that expected from a central transit of a low-eccentricity planet says that the planet must be slower (and hence farther from its primary) at that moment than expected at any time in a low-eccentricity orbit, and so its eccentricity must be high. However, a transit duration less than the expected duration of a central transit and a low-eccentricity orbit means little, since the transit might be off-center or grazing, which would reduce its duration as well. Perhaps in principle a transit can be determined to be off-center if we time the steepness of the light curve's descent/ascent. I'm unsure though that Kepler would have the requisite time resolution. Brian, it looks like an Earth-Sun analogue would have a few times less radial velocity than would be needed, though one might get close if the star was near and bright with lots of photons. Syrinx, I was at a similar launch party at CU/LASP where the mission is being controlled from. I gather most of the science activity will be at Ames. -------------------- Steve [ my home page and planetary maps page ]
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Mar 8 2009, 09:09 PM
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#89
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Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
- What if a star just happens to be right on the border of one pixel and another pixel? Kepler blurs adjacent pixels to account for this. (Not clear to me if this is accomplished in software or hardware.) Syrinx, my understanding is that star images are deliberately unfocused at sensor and their blurred images are about 7 pixel wide. This "hardware blur" offers many advantages in terms of precison and dynamic range because it reduces effect of different pixel responses and avoid fast saturation... Take in mind that Kepler camera is not used to took real pictures ( ) but only extremely accurate photometry of selected stars in the field. -------------------- I always think before posting! - Marco -
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Mar 10 2009, 05:18 PM
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#90
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Junior Member Group: Members Posts: 55 Joined: 1-May 06 From: Cincinnati, Ohio Member No.: 758 |
I am an engineer for MAG Cincinnati (formerly Cincinnati Machine) and we built a large vertical milling machine which was used as a grinder to grind the 1.4 meter diameter photometer mirror for Kepler. The U5 machine was built for L-3 Communications (Brashear) who performed the work for NASA.
So I say bon voyage to Kepler and use your mirror well! Catch a few Earth-sized objects!!! Rob |
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Guest_PhilCo126_* |
Mar 10 2009, 06:33 PM
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#91
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Guests |
Talking about mission life time; there was already talk of a possible extension to six years, which would allow improved observations of more transits to detect smaller planets and of course finding planets in larger period orbits
Meanwhile: http://www.astronomynow.com/090310KeckandK...joinforces.html |
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Mar 10 2009, 10:39 PM
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#92
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Member Group: Members Posts: 237 Joined: 22-December 07 From: Alice Springs, N.T. Australia Member No.: 3989 |
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Mar 10 2009, 10:46 PM
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#93
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Senior Member Group: Members Posts: 1452 Joined: 26-July 08 Member No.: 4270 |
Ref the article: Interesting!!! Especially ..... "Furthermore, Marcy and his team can use the Keck-calculated mass and Kepler-calculated diameter to determine the planet's density". (My bolding) I am unsure why you bring attention to this. Density = mass / volume, with the mass and volume of a planet, we can calculate its density fairly easily. The density of transiting planets is not unmeasured. To name a few examples: HD 209458 b -> ~ 0.41 g cm^-3. HD 149026 b -> ~ 0.82 g cm^-3. HAT-P-2 b -> ~11.9 g cm^-3. HD 189733 b -> ~ 1.06 g cm^-3. TrES-3 b -> ~ 0.99 g cm^-3. And so on... -------------------- -- Hungry4info (Sirius_Alpha)
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Mar 11 2009, 09:32 AM
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#94
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Member Group: Members Posts: 593 Joined: 20-April 05 Member No.: 279 |
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Mar 11 2009, 10:57 AM
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#95
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Member Group: Members Posts: 237 Joined: 22-December 07 From: Alice Springs, N.T. Australia Member No.: 3989 |
I am unsure why you bring attention to this. As I understand it (being an interested amateur) the radius of planets can only be determined from the shape of their light curves using transiting techniques. Since Kepler will be in space and has such an advanced photometer, it will be able to determine the size of planets that are even smaller than Earth. It will simultaneously observe a huge number of stars - 100,000. Before reading the article I didn't realize that there was any radial velocity technique sensitive enough to check out the mass of such small planets. Since Keck has the capability to detect changes in radial velocity down to below 1/m sec, it is senstive enough. It will target the transit positives. So you were right to comment!!! Currently we only know the size and and mass of a small percentage of planets - the new Planetary Society exoplanet catalogue is really useful resource. What I should have said was ...... density of (hopefully a lot of) earth like planets!!!. That's exciting. How many will be around the 5.75 gm/cc? I believe radial velocity techniques currently only estimate min mass with + ~20% error range to more heavy than estimated - worse if not in line of site. PS - Andy - TPS catalogue gives HAT-P-2 b density ~13.37 gm/cc!! 'Super Earth' CoRoT-Exo-7b density ~11.36 gm/cc!! |
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Mar 11 2009, 02:22 PM
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#96
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Member Group: Members Posts: 279 Joined: 19-August 07 Member No.: 3299 |
... can use the Keck-calculated mass ... That has brought to my attention. How does the team determine its mass? Using the mass spectometry determines it? If it is so, which of the following method uses: a) Vaporisation 'b)' Ionisation c) Acceleration d) Deflection e) Detection Regards, |
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Mar 11 2009, 03:50 PM
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#97
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Senior Member Group: Members Posts: 2492 Joined: 15-January 05 From: center Italy Member No.: 150 |
SpaceListener, I hope you're jocking...
If you are able to put an exoplanet inside a mass spectrometer, you are a genius! -------------------- I always think before posting! - Marco -
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Mar 11 2009, 05:11 PM
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#98
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Founder Group: Chairman Posts: 14434 Joined: 8-February 04 Member No.: 1 |
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Guest_PhilCo126_* |
Mar 12 2009, 08:58 AM
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#99
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Guests |
Correct Doug... examining the star's (periodic) radial velocity(ies) reveals the mass(es) of exo-planet(s).
AdyG --> http://en.wikipedia.org/wiki/HAT-P-2b Multiple exo-planets: |
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Mar 12 2009, 11:23 AM
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#100
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Member Group: Members Posts: 128 Joined: 10-December 06 From: Atlanta Member No.: 1472 |
Correct Doug... examining the star's (periodic) radial velocity(ies) reveals the mass(es) of exo-planet(s). Using radial velocity technique, one can calculate m.sin(i), where m is the mass and i the orbital inclination (for one or more planets). Hence, the radial velocity only determines a lower limit on the mass. If an exoplanet is observed by both radial velocity and transit method, it means i=90 (due to seeing a transit), and that fixed the mass. Planet radius can be calculated by transit method. Therefore, using a combination of radial velocity and transit methods, it is possible to calculate the density (but neither does it alone). |
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