Kepler News and Results

Edit: Even though results from Kepler will take a while to come out (for understandable reasons), I feel it's time to make a thread about Kepler results. If nothing else because the Kepler preparation thread isn't covering the spacecraft's preparation anymore... the thing is launched, in space now, and in commissioning. As such, I've moved the post that started with Kepler's "first light" (even though the dust cover is still on for now) and the post after that to this new thread. Now we'll let Kepler and CoRoT race to 100 planets.

Kepler achieves First Light

http://beyondthecradle.wordpress.com/2009/03/26/kepler-mission-first-light-update-with-jon-jenkins/

Kepler has entered safe mode. Here's an update from the Kepler News website.

Quote :

2009 March 30. Mission Manager Update - Engineers have determined the cause of Kepler's entry into limited safe mode last week, and are preparing to return the spacecraft to normal operations. In order for Kepler to know where it is in space, and to know where to point its high-gain antenna toward Earth, the spacecraft maintains information about its position, called a state vector, which update ten times per second. Every few days, navigators on the ground update their knowledge of Kepler's actual orbit, and ground controllers upload a new state vector to the spacecraft. Engineers have concluded that, if the new state vector's start time is a multiple of 1,000 seconds from the start time of the previous vector, a momentary glitch occurs in the calculated spacecraft attitude. Even though this only lasts for one-tenth of a second, the spacecraft senses something it didn't expect and responds by pointing its solar arrays directly at the sun and awaiting further instructions from Earth. It will take a few days to ensure that everything is ready to proceed with commissioning, the next major step being release of the telescope's dust cover. March 30 14:00 UTC - Distance to Kepler: 2,362,000 km; 1,467,000 mi; 0.016 AU; 6.14 times the distance to the Moon.

Dust cover is now off.

Calibration with starlight continues.

Science data approx 2 weeks away.

First light image! Here's part of it (what cluster is that?)



Edit: Turns out the cluster is NGC 6791

According to its WEBDA entry, NGC 6791 has an age of 10^9.643 years = 4.4 billion years, and a metallicity of +0.15 = 140% solar.

Interesting target...

Space.com provides a preview of the full Kepler FOV.



This region is going to be under a lot of scrutiny for planets in the next 3.5 years.

At this url, there are several more images, also with links to full resolution Kepler FOV images.

There's another fairly old and metal-rich open cluster in the Kepler FOV, NGC 6819 has log age = 9.174 (=1.5 billion years), [Fe/H]=+0.07 (=120% solar). Be interesting if planetary systems can form/survive in such an environment for long periods of time, a planet in an open cluster would have a fairly spectacular night sky.

Now that the discovery of such a cool star as Wolf 940 B has finally made it to the news websites, it seems Kepler has found many cooler stars. Perhaps with temperatures low enough to be Earth-like.

Telescope finds 100,000 possible Earth-like stars
http://www.denverpost.com/business/ci_12160163
(emphasis mine)

http://kepler.nasa.gov/about/news.html

Quote :

2009 May 1. Mission Manager Update - Kepler's calibration data collection is drawing to a close. Several hundred data sets have been acquired to characterize and map the optical and noise performance of the telescope and the electronics for the focal plane array (the area where light is focused). The data sets are now being analyzed on the ground. Optimally shaped "windows" of pixels will be defined for each of the more than 100,000 target stars and a table of these pixels uploaded to the spacecraft. These are the pixels that will ultimately help the science team find planets -- the pixels will be downlinked to Earth and used to construct light curves, or measurements of brightness over time, for each star.
After science observations begin, the data analysis "pipeline" at the Science Operations Center at NASA's Ames Research Center in Moffett Field, Calif., will process the light curves to identify "threshold crossing events," which is the first step in identifying potential transiting planets. Various tests will be applied to these events to weed out false indications. Once confidence is built for candidate transits, observations by ground-based telescopes will be performed to further rule out phenomena that can masquerade as transiting planets.

Quote :

2009 May 7. Mission Manager Update - Kepler is now more than six million kilometers (3.7 million miles) from Earth, with a round-trip light time -- the time it takes a command to reach the spacecraft and a response to return to Earth -- of 40 seconds. The final performance data are being collected to assess the sensitivity of the science instrument. This will determine how well Kepler will be able to measure the transits of small planets like Earth.
The operations team no longer communicates around the clock with Kepler; contact through NASA's Deep Space Network is reduced to about 18 hours per day and will soon drop to about 6 hours per day when science observations begin. This is a gradual transition to the mode of operation planned for the remainder of the mission, when communication will occur only twice per week. The project will convene a science operations readiness review on Monday, May 11, to determine if the team is ready to commence science data collection.

Kepler begins science observations:

http://kepler.nasa.gov/about/news.html

A somewhat provocative blog post from Steinn Sigurðsson at Dynamics of Cats.

http://www.nasa.gov/mission_pages/kepler/news/keplerm-20090619.html

Quote :

Kepler Mission Manager Update
06.19.09
Roger Hunter, Kepler-Ames Mission Manager Kepler is more than 10,700,000 kilometers (about 6,600,00 miles) from Earth and continues its planned drift-away orbit. Since May 12, 2009, Kepler has been observing its target region near the Cygnus constellation. Today, data collected continuously since science operations began on May 12, 2009 were downloaded to the Kepler Science Operations Center at Ames Research Center, Moffett Field, Calif. The data were collected from observing over 145,000 stars simultaneously. Scientists will begin in earnest the analysis of this data to search for other Earth-size planets. Engineers also completed Kepler's planned quarterly roll. This roll will ensure that Kepler's solar arrays are kept optimally positioned with respect to our sun, to ensure proper power generation, for the next three months. Both the science data download, and the quarterly roll, are Kepler "firsts" in its planned three-and-a-half-year mission.
On June 15, 2009, Kepler entered safe mode, a protocol executed by the spacecraft as a precautionary safety feature. In this case, the safe mode entry was caused by a fault in part of the spacecraft processor. Upon detection of the entry into safe mode, engineers began anomaly response procedures to determine spacecraft health and status, cause of the fault, and recovery. Engineers determined the spacecraft's stored science data was safe. The fault caused the Kepler photometer to turn off. Further analysis indicated the Kepler subsystems were not endangered by the fault. Engineers re-initialized the photometer, downlinked the science data, performed the quarterly roll, and returned the spacecraft to its mission. Analysis will continue on spacecraft telemetry files to better understand the root cause of the safe-mode event. The mission baseline allows for 12 days per year for potential safe-mode events such as this one. This particular event consumed about one-and-a-half days of what would have been time collecting science data. In mission dress rehearsals prior to launch, the Kepler team practiced responses to non-nominal conditions, like safe-mode events and spacecraft malfunctions. Thanks to this practice, the team responded effectively and efficiently to restore Kepler to its nominal operational status. Twice-per-week routine contacts with the Kepler spacecraft will resume, as Kepler collects another 30 days of science data in its hunt for Earth-like planets. The next science data download will occur in late July.

Guess they got a blur screen of death situation!!

So in addition to the 12 days already being lost for antenna orientation maneuvers
we are also likely to loose at least 12 more days to various technical faults.

That is roughly 10% of the time annually.

There should therefore be a 30% chance that at least one transit of a potential earth orbit
exoplanet might get missed. The original mission plan called for Kepler to then look at another
patch of the sky. This is looking highly unlikely now as the pressure to catch that third orbit
is likely to be overwhelming.

What does everyone else think?

The safe-mode event took up only 1.5 days, out of the 12 they're allotted (though I don't see why they have a limited amount of time).

Where do you get that the spacecraft takes 12 days to do its quarter turn? I'm not spaceflight expert, but I would imagine it would take no more than a minute or two.

AFAIK, Kepler will look at the same spot of the sky indefinitely to extend the range of planets that can be detected to increasingly large orbital periods, and thus semi-major axes. As Kepler's mission is to do an exoplanet census, you really want to sample planets across as wide a range of semi-major axes as possible. It would just make sense then, to stare at the same amount of sky as long as possible. Looking at new patch would add a bunch of new hot Jupiters, but would compromise the potential value of the census.

I think that as long as Kepler is able, it should continue to stare at the Cygnus region. Keep staring at it until it's photometric eyes bleed. Catch all those transiting planets, not just the short period ones.

http://kepler.nasa.gov/about/history.html

The eighth item on the list details a cost cutting strategy of eliminating the antenna gimbal costing about a day per month.

I doubt the antenna data rate can download a months worth of thousands of high rez pictures in a few minutes!

I was hoping that it could then be pointed to closer in stars to check them for planets. This would be a more poignant search IMHO.

Especially now that TESS is a gonner to (trying not to get impatient here! All projects are important) projects such as the determining yet another layer of the Sun and some X-Rays from Neutron Stars and Black Holes.

TheoA wrote:

I doubt the antenna data rate can download a months worth of thousands of high rez pictures in a few minutes!

Forgive me, but does the Kepler photometer send back thousands of high-resolution images of the Cygnus field? Or does it just measure light curves and send those back? I would imagine the later would be much more efficient. I'm not sure quite how that works.

Sirius, you are correct.

Apparently only the relevant 'designated' pixels are downloaded.

Still it should be more than mere minutes.. ...a few hours maybe?

I any case the chances of a secondary mission are pretty dim.

I've heard talk about an extension to the Kepler mission being a possibility. It's target field aside, if Kepler does yield significant finds, maybe they might be granted an extension? I'd love Kepler to last forever, but I realise NASA doesn't exactly have a lot of cash.

However... if Kepler funding will be needed to go to development of SIM or (if my greatest hopes and dreams are realised) TPF, then let it be.

http://kepler.nasa.gov/about/manager.html (July 7th, update)

These resets are unfortunate.

The note says it was a processor reset, same as the last one.

Hopefully it is not a hardware failure.

I assume repairs would be out of the question.

Repairs are out of the question since Kepler is not in LEO, the only 'space' accessible by the crewed space shuttle. Kepler is in a 1 AU solar orbit, continually 'falling behind' the Earth.

Mission manager update

http://kepler.nasa.gov/about/manager.html

Lots of interesting details.

They are now checking every day for anomalies.

Next down load is delayed to August 20 2009.

An incredible 50 Gbits of data was downloaded on the last link.
IIRC correctly Galileo returned 30 or Gbytes or so over 8 years
admittedly with a crippled antennae!

There is still no info on how long the outage lasted.
The telescope could very easily have been down for a week.

The July 2nd outage detection was resolved a day later. According to the July 7th report, "By late July 3, Kepler had returned to normal science operations." Prior to July 2nd, data was downoaded on June 19th. Assuming it entered safe mode on the 20th and somehow this went undetected, worst case is that all observational data until July 2nd could have been lost. Thanks for posting the updates.