NASA - NASA Ends Attempts to Fully Recover Kepler Spacecraft, Potential New Missions Considered

NASA Ends Attempts to Fully Recover Kepler Spacecraft, Potential New Missions Considered

Following months of analysis and testing, the Kepler Space Telescope team is ending its attempts to restore the spacecraft to full working order, and now is considering what new science research it can carry out in its current condition.

Two of Kepler's four gyroscope-like reaction wheels, which are used to precisely point the spacecraft, have failed. The first was lost in July 2012, and the second in May. Engineers' efforts to restore at least one of the wheels have been unsuccessful.

Kepler completed its prime mission in November 2012 and began its four-year extended mission at that time. However, the spacecraft needs three functioning wheels to continue its search for Earth-sized exoplanets, which are planets outside our solar system, orbiting stars like our sun in what's known as the habitable zone -- the range of distances from a star where the surface temperature of a planet might be suitable for liquid water. As scientists analyze previously collected data, the Kepler team also is looking into whether the space telescope can conduct a different type of science program, including an exoplanet search, using the remaining two good reaction wheels and thrusters.

"Kepler has made extraordinary discoveries in finding exoplanets including several super-Earths in the habitable zone," said John Grunsfeld, associate administrator for NASA's Science Mission Directorate in Washington. "Knowing that Kepler has successfully collected all the data from its prime mission, I am confident that more amazing discoveries are on the horizon."

On Aug. 8, engineers conducted a system-level performance test to evaluate Kepler's current capabilities. They determined wheel 2, which failed last year, can no longer provide the precision pointing necessary for science data collection. The spacecraft was returned to its point rest state, which is a stable configuration where Kepler uses thrusters to control its pointing with minimal fuel use.

"At the beginning of our mission, no one knew if Earth-size planets were abundant in the galaxy. If they were rare, we might be alone," said William Borucki, Kepler science principal investigator at NASA's Ames Research Center in Moffett Field, Calif. "Now at the completion of Kepler observations, the data holds the answer to the question that inspired the mission: Are Earths in the habitable zone of stars like our sun common or rare?

An engineering study will be conducted on the modifications required to manage science operations with the spacecraft using a combination of its remaining two good reaction wheels and thrusters for spacecraft attitude control.

Informed by contributions from the broader science community in response to the call for scientific white papers announced Aug. 2, the Kepler project team will perform a study to identify possible science opportunities for a two-wheel Kepler mission.

Depending on the outcome of these studies, which are expected to be completed later this year, NASA will assess the scientific priority of a two-wheel Kepler mission. Such an assessment may include prioritization relative to other NASA astrophysics missions competing for operational funding at the NASA Senior Review board early next year.

From the data collected in the first half of its mission, Kepler has confirmed 135 exoplanets and identified over 3,500 candidates. The team continues to analyze all four years of collected data, expecting hundreds, if not thousands, of new discoveries including the long-awaited Earth-size planets in the habitable zone of sun-like stars. Though the spacecraft will no longer operate with its unparalleled precision pointing, scientists expect Kepler’s most interesting discoveries are still to come. 

Meanwhile, preparations are underway for hosting the second Kepler Science Conference Nov. 4-8, at NASA's Ames Research Center. This will be an opportunity to share not only the investigations of the Kepler project team, but also those of the wider science community using publicly accessible data from Kepler. Registration is now open. For more information about Kepler's upcoming science conference, visit:

http://go.nasa.gov/13kz012

For more information about NASA's call for two-wheel science proposals, visit:

http://go.nasa.gov/1a1UzaC

For more information about NASA's Kepler spacecraft, visit:

http://www.nasa.gov/kepler

NASA

Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com

ayabaca@hotmail.com

ayabaca@yahoo.com

Astronomy: NASA's Kepler Releases New Catalog- 2,321 Planet Candidates

Hi My Friends: AL VUELO DE UN QUINDE EL BLOG., The histogram summarizes the findings in the Feb. 27, 2012 Kepler Planet Candidate catalog release. The catalog contains 2,321 planet candidates identified during the first 16 months of observation conducted May 2009 to September 2010. Of the 46 planet candidates found in the habitable zone, the region in the planetary system where liquid water could exist, ten of these candidates are near-Earth-size. Kepler Planet Candidates by Size, Feb. 27, 2012
The histogram summarizes the findings in the Feb. 27, 2012 Kepler Planet Candidate catalog release. The catalog contains 2,321 planet candidates identified during the first 16 months of observation conducted May 2009 to September 2010. Of the 46 planet candidates found in the habitable zone, the region in the planetary system where liquid water could exist, ten of these candidates are near-Earth-size.

Credit: NASA Ames/Wendy Stenzel.

Since science operations began in May 2009, the Kepler team has released two catalogs of transiting planet candidates. The first catalog (Borucki et al, 2010), released in June 2010, contains 312 candidates identified in the first 43 days of Kepler data. The second catalog (Borucki et al, 2011), released in February 2011, is a cumulative catalog containing 1,235 candidates identified in the first 13 months of data.

Today the team presents the third catalog containing 1,091 new planet candidates identified in the first 16 months of observation conducted May 2009 to September 2010. These are the same candidates that the team discussed at the Kepler Science Conference held at NASA Ames Research Center in December 2011.

Here are the highlights of the new catalog:
A.- Planet candidates smaller than twice the size of Earth increased by 197 percent, compared to 52 percent for candidates larger than twice the size of Earth.
B.- Planet candidates with orbital periods longer than 50 days increased by 123 percent, compared to 85 percent for candidates with orbital periods shorter than 50 days. Since the last catalog was released in February 2011, the number of planet candidates identified by Kepler has increased by 88 percent and now totals 2,321 transiting 1,790 stars.

The cumulative catalog now contains well over 200 Earth-size planet candidates and more than 900 that are smaller than twice Earth-size. Of the 46 planet candidates found in the habitable zone, the region in the planetary system where liquid water could exist, ten of these candidates are near-Earth-size.

The number of planetary systems found with more than one planet candidate also has increased. Last year, 17 percent, or 170 stars, had more than one transiting planet candidate. Today, 20 percent, or 365, stars have more than one.

"With each new catalog release a clear progression toward smaller planets at longer orbital periods is emerging, " said Natalie Batalha, Kepler deputy science team lead at San Jose State University in California. "This suggests that Earth-size planets in the habitable zone are forthcoming if, indeed, such planets are abundant.

"Nearly 5,000 periodic transit-like signals were analyzed with known spacecraft instrumentation and astrophysical phenomena that could masquerade as transits, which can produce false positives. The most common false positive signatures are associated with eclipsing binary stars- a pair of orbiting stars that eclipse each other from the vantage point of the spacecraft.

The Kepler space telescope identifies planet candidates by repeatedly measuring the change in brightness of more than 150,000 stars in search of planets that pass in front, or "transit," their host star. Kepler must record at least three transits to verify a signal as a planet.

The findings are published in the "Planetary Candidates Observed by Kepler III: Analysis of the First 16 Months of Data".

The catalog is available at the Kepler data archive at the Space Telescope Science Institute and can be downloaded from the NASA Exoplanet Archive.

NASA's Ames Research Center in Moffett Field, Calif., manages Kepler's ground system development, mission operations and science data analysis. NASA’s Jet Propulsion Laboratory, Pasadena, Calif., managed the Kepler mission's development.

Ball Aerospace and Technologies Corp. in Boulder, Colo., developed the Kepler flight system and supports mission operations with the Laboratory for Atmospheric and Space Physics at the University of Colorado in Boulder.

The Space Telescope Science Institute in Baltimore archives, hosts and distributes Kepler science data. Kepler is NASA's 10th Discovery Mission and is funded by NASA's Science Mission Directorate at the agency's headquarters in Washington.

For information about the Kepler Mission,

visit: http://www.nasa.gov/kepler
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com

ayabaca@hotmail.com

ayabaca@yahoo.com

Astronomy: NASA's Kepler Mission Finds Three Smallest Exoplanets

Hi My Friends: AL VUELO DE UN QUINDE EL BLOG., Astronomers using data from NASA's Kepler mission have discovered the three smallest planets yet detected orbiting a star beyond our sun. The planets orbit a single star, called KOI-961, and are 0.78, 0.73 and 0.57 times the radius of Earth. The smallest is about the size of Mars.

Mini Planetary System
This artist's concept depicts an itsy bitsy planetary system -- so compact, in fact, that it's more like Jupiter and its moons than a star and its planets. Astronomers using data from NASA's Kepler mission and ground-based telescopes recently confirmed that the system, called KOI-961, hosts the three smallest exoplanets known so far to orbit a star other than our sun. An exoplanet is a planet that resides outside of our solar system.

The star, which is located about 130 light-years away in the Cygnus constellation, is what's called a red dwarf. It's one-sixth the size of the sun, or just 70 percent bigger than Jupiter. The star is also cooler than our sun, and gives off more red light than yellow.

The smallest of the three planets, called KOI-961.03, is actually located the farthest from the star, and is pictured in the foreground. This planet is about the same size as Mars, with a radius only 0.57 times that of Earth. The next planet to the upper right is KOI-961.01, which is 0.78 times the radius of Earth. The planet closest to the star is KOI-961.02, with a radius 0.73 times the Earth's.

All three planets whip around the star in less than two days, with the closest planet taking less than half a day. Their close proximity to the star also means they are scorching hot, with temperatures ranging from 350 to 836 degrees Fahrenheit (176 to 447 degrees Celsius). The star's habitable zone, or the region where liquid water could exist, is located far beyond the planets.

The ground-based observations contributing to these discoveries were made with the Palomar Observatory, near San Diego, Calif., and the W.M. Keck Observatory atop Mauna Kea in Hawaii.

Image credit: NASA/JPL-Caltech

Sizing Up Exoplanets
This chart compares the smallest known exoplanets, or planets orbiting outside the solar system, to our own planets Mars and Earth. Astronomers using data from NASA's Kepler mission and ground-based telescopes recently discovered the three smallest exoplanets known to circle another star, called KOI-961.01, KOI-961.02 and KOI-961.03.

The smallest of these, KOI-961.03, is about the size of Mars with a radius of only 0.57 times that of Earth. Not long ago, in Dec. of 2011, the Kepler team announced the discovery of Kepler-20e and Kepler-20f -- the first Earth-size planets ever found outside the solar system.

All five of these small exoplanets have toasty orbits close to their stars, and do not lie in the more temperate habitable zone.The ground-based observations contributing to the KOI-961 discoveries were made with the Palomar Observatory, near San Diego, Calif., and the W.M. Keck Observatory atop Mauna Kea in Hawaii.

Image credit: NASA/JPL-Caltech

'Honey I Shrunk the Planetary System'
This artist's conception compares the KOI-961 planetary system to Jupiter and the largest four of its many moons. The KOI-961 planetary system hosts the three smallest planets known to orbit a star beyond our sun (called KOI-961.01, KOI-961.02 and KOI-961.03).

The smallest of these planets, KOI-961.03, is about the same size as Mars. All three planets take less than two days to whip around their star.

The planets were discovered using data from NASA's Kepler mission and ground-based telescopes. The KOI-961 star is a tiny "red dwarf," just one-sixth the size of our sun. This planetary system is the most compact detected to date, with a scale closer to Jupiter and its moons than another star system.

The planet and moon orbits are drawn to the same scale. The relative sizes of the stars, planets and moons have been increased for visibility.
Image credit: Caltech
Astronomers using data from NASA's Kepler mission have discovered the three smallest planets yet detected orbiting a star beyond our sun. The planets orbit a single star, called KOI-961, and are 0.78, 0.73 and 0.57 times the radius of Earth. The smallest is about the size of Mars.

All three planets are thought to be rocky like Earth, but orbit close to their star. That makes them too hot to be in the habitable zone, which is the region where liquid water could exist. Of the more than 700 planets confirmed to orbit other stars -- called exoplanets -- only a handful are known to be rocky.

"Astronomers are just beginning to confirm thousands of planet candidates uncovered by Kepler so far," said Doug Hudgins, Kepler program scientist at NASA Headquarters in Washington." Finding one as small as Mars is amazing, and hints that there may be a bounty of rocky planets all around us."

Kepler searches for planets by continuously monitoring more than 150,000 stars, looking for telltale dips in their brightness caused by crossing, or transiting, planets. At least three transits are required to verify a signal as a planet. Follow-up observations from ground-based telescopes also are needed to confirm the discoveries.

The latest discovery comes from a team led by astronomers at the California Institute of Technology in Pasadena. The team used data publicly released by the Kepler mission, along with follow-up observations from the Palomar Observatory, near San Diego, and the W.M. Keck Observatory atop Mauna Kea in Hawaii. Their measurements dramatically revised the sizes of the planets from what originally was estimated.

The three planets are very close to their star, taking less than two days to orbit around it. The KOI-961 star is a red dwarf with a diameter one-sixth that of our sun, making it just 70 percent bigger than Jupiter.

"This is the tiniest solar system found so far," said John Johnson, the principal investigator of the research from NASA's Exoplanet Science Institute at the California Institute of Technology in Pasadena. "It's actually more similar to Jupiter and its moons in scale than any other planetary system. The discovery is further proof of the diversity of planetary systems in our galaxy."

Red dwarfs are the most common kind of star in our Milky Way galaxy. The discovery of three rocky planets around one red dwarf suggests that the galaxy could be teeming with similar rocky planets.

"These types of systems could be ubiquitous in the universe," said Phil Muirhead, lead author of the new study from Caltech. "This is a really exciting time for planet hunters.

"The discovery follows a string of recent milestones for the Kepler mission. In December 2011, scientists announced the mission's first confirmed planet in the habitable zone of a sun-like star: a planet 2.4 times the size of Earth called Kepler-22b. Later in the month, the team announced the discovery of the first Earth-size planets orbiting a sun-like star outside our solar system, called Kepler-20e and Kepler-20f.

For the latest discovery, the team obtained the sizes of the three planets called KOI-961.01, KOI-961.02 and KOI-961.03 with the help of a well-studied twin star to KOI-961, or Barnard's Star. By better understanding the KOI-961 star, they then could determine how big the planets must be to have caused the observed dips in starlight. In addition to the Kepler observations and ground-based telescope measurements, the team used modeling techniques to confirm the planet discoveries.

Prior to these confirmed planets, only six other planets had been confirmed using the Kepler public data.

NASA's Ames Research Center in Moffett Field, Calif., manages Kepler's ground system development, mission operations and science data analysis. NASA’s Jet Propulsion Laboratory, Pasadena, Calif., managed the Kepler mission's development.For information about the Kepler Mission, visit:
http://www.nasa.gov/kepler
http://www.nasa.gov/mission_pages/kepler/main/index.html

NASA
Guillermo Gonzalo Sánchez Achutegui

ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com