MOFFET FIELD, Calif. — NASA’s Kepler mission has discovered the first Earth-size planets orbiting a sun-like star outside our solar system. The planets, called Kepler-20e and Kepler-20f, are too close to their star to be in the so-called habitable zone where liquid water could exist on a planet’s surface, but they are the smallest exoplanets ever confirmed around a star like our sun.

The discovery marks the next important milestone in the ultimate search for planets like Earth. The new planets are thought to be rocky. Kepler-20e is slightly smaller than Venus, measuring 0.87 times the radius of Earth. Kepler-20f is a bit larger than Earth, measuring 1.03 times its radius. Both planets reside in a five-planet system called Kepler-20, approximately 1,000 light-years away in the constellation Lyra.

Kepler-20e orbits its parent star every 6.1 days and Kepler-20f every 19.6 days. These short orbital periods mean very hot, inhospitable worlds. Kepler-20f, at 800 degrees Fahrenheit, is similar to an average day on the planet Mercury. The surface temperature of Kepler-20e, at more than 1,400 degrees Fahrenheit, would melt glass.

“The primary goal of the Kepler mission is to find Earth-sized planets in the habitable zone,” said Francois Fressin of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., lead author of a new study published in the journal Nature. “This discovery demonstrates for the first time that Earth-size planets exist around other stars, and that we are able to detect them.”

The Kepler-20 system includes three other planets that are larger than Earth but smaller than Neptune. Kepler-20b, the closest planet, Kepler-20c, the third planet, and Kepler-20d, the fifth planet, orbit their star every 3.7, 10.9 and 77.6 days. All five planets have orbits lying roughly within Mercury’s orbit in our solar system. The host star belongs to the same G-type class as our sun, although it is slightly smaller and cooler.

The system has an unexpected arrangement. In our solar system, small, rocky worlds orbit close to the sun and large, gaseous worlds orbit farther out. In comparison, the planets of Kepler-20 are organized in alternating size: large, small, large, small and large.

“The Kepler data are showing us some planetary systems have arrangements of planets very different from that seen in our solar system,” said Jack Lissauer, planetary scientist and Kepler science team member at NASA’s Ames Research Center in Moffett Field, Calif. “The analysis of Kepler data continue to reveal new insights about the diversity of planets and planetary systems within our galaxy.”

Scientists are not certain how the system evolved but they do not think the planets formed in their existing locations. They theorize the planets formed farther from their star and then migrated inward, likely through interactions with the disk of material from which they originated. This allowed the worlds to maintain their regular spacing despite alternating sizes.

The Kepler space telescope detects planets and planet candidates by measuring dips in the brightness of more than 150,000 stars to search for planets crossing in front, or transiting, their stars. The Kepler science team requires at least three transits to verify a signal as a planet.

The Kepler science team uses ground-based telescopes and the Spitzer Space Telescope to review observations on planet candidates the spacecraft finds. The star field Kepler observes in the constellations Cygnus and Lyra can be seen only from ground-based observatories in spring through early fall. The data from these other observations help determine which candidates can be validated as planets.

To validate Kepler-20e and Kepler-20f, astronomers used a computer program called Blender, which runs simulations to help rule out other astrophysical phenomena masquerading as a planet.

On Dec. 5 the team announced the discovery of Kepler-22b in the habitable zone of its parent star. It is likely to be too large to have a rocky surface. While Kepler-20e and Kepler-20f are Earth-size, they are too close to their parent star to have liquid water on the surface.

“In the cosmic game of hide and seek, finding planets with just the right size and just the right temperature seems only a matter of time,” said Natalie Batalha, Kepler deputy science team lead and professor of astronomy and physics at San Jose State University. “We are on the edge of our seats knowing that Kepler’s most anticipated discoveries are still to come.”

NASA’s Ames Research Center in Moffett Field, Calif., manages Kepler’s ground system development, mission operations and science data analysis. JPL 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 more information about the Kepler mission and to view the digital press kit, visit: http://www.nasa.gov/kepler

CAPE CANAVERAL, Fla. — NASA began a historic voyage to Mars with the Nov. 26 launch of the Mars Science Laboratory, which carries a car-sized rover named Curiosity. Liftoff from Cape Canaveral Air Force Station aboard an Atlas V rocket occurred at 10:02 a.m. EST (7:02 a.m. PST).
“We are very excited about sending the world’s most advanced scientific laboratory to Mars,” NASA Administrator Charles Bolden said. “MSL will tell us critical things we need to know about Mars, and while it advances science, we’ll be working on the capabilities for a human mission to the Red Planet and to other destinations where we’ve never been.”

The mission will pioneer precision landing technology and a sky-crane touchdown to place Curiosity near the foot of a mountain inside Gale Crater on Aug. 6, 2012. During a nearly two-year prime mission after landing, the rover will investigate whether the region has ever offered conditions favorable for microbial life, including the chemical ingredients for life.

“The launch vehicle has given us a great injection into our trajectory, and we’re on our way to Mars,” said Mars Science Laboratory Project Manager Peter Theisinger of NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “The spacecraft is in communication, thermally stable and power positive.”

The Atlas V initially lofted the spacecraft into Earth orbit and then, with a second burst from the vehicle’s upper stage, pushed it out of Earth orbit into a 352-million-mile (567-million-kilometer) journey to Mars.

“Our first trajectory correction maneuver will be in about two weeks,” Theisinger said. “We’ll do instrument checkouts in the next several weeks and continue with thorough preparations for the landing on Mars and operations on the surface.”

Curiosity’s ambitious science goals are among the mission’s many differences from earlier Mars rovers. It will use a drill and scoop at the end of its robotic arm to gather soil and powdered samples of rock interiors, then sieve and parcel out these samples into analytical laboratory instruments inside the rover. Curiosity carries 10 science instruments with a total mass 15 times as large as the science-instrument payloads on the Mars rovers Spirit and Opportunity. Some of the tools are the first of their kind on Mars, such as a laser-firing instrument for checking the elemental composition of rocks from a distance, and an X-ray diffraction instrument for definitive identification of minerals in powdered samples.

To haul and wield its science payload, Curiosity is twice as long and five times as heavy as Spirit or Opportunity. Because of its one-ton mass, Curiosity is too heavy to employ airbags to cushion its landing as previous Mars rovers could. Part of the Mars Science Laboratory spacecraft is a rocket-powered descent stage that will lower the rover on tethers as the rocket engines control the speed of descent.

The mission’s landing site offers Curiosity access for driving to layers of the mountain inside Gale Crater. Observations from orbit have identified clay and sulfate minerals in the lower layers, indicating a wet history.

Precision landing maneuvers as the spacecraft flies through the Martian atmosphere before opening its parachute make Gale a safe target for the first time. This innovation shrinks the target area to less than one-fourth the size of earlier Mars landing targets. Without it, rough terrain at the edges of Curiosity’s target would make the site unacceptably hazardous.

The innovations for landing a heavier spacecraft with greater precision are steps in technology development for human Mars missions. In addition, Curiosity carries an instrument for monitoring the natural radiation environment on Mars, important information for designing human Mars missions that protect astronauts’ health.

The mission is managed by JPL, a division of the California Institute of Technology in Pasadena, for NASA’s Science Mission Directorate in Washington. The rover was designed, developed and assembled at JPL. NASA’s Launch Services Program at the Kennedy Space Center in Florida managed the launch. NASA’s Space Network provided space communication services for the launch vehicle. NASA’s Deep Space Network will provide spacecraft acquisition and mission communication.

For more information about the mission, visit: http://www.nasa.gov/msl and http://marsprogram.jpl.nasa.gov/msl/ .

For more information about the Deep Space Network, visit:

Less than a month after NASA’s falling UARS satellite grabbed the headlines, the German space agency says one of its abandoned satellites will dive back to Earth later this month, but no one knows where it will land.

The ROSAT X-ray astronomy observatory is smaller and less massive than NASA’s Upper Atmospheric Research Satellite, or UARS, which fell back to Earth on Sept. 24. But officials predict it will spread three times more debris and pose a greater threat to people than UARS.

That’s because ROSAT is made of heat-resistant components, especially its primary mirror, which officials say will probably be the largest single fragment that will reach Earth.

The satellite will streak into the atmosphere at 17,000 mph, and temperatures up to 3,000 degrees Fahrenheit will burn up much of the spacecraft.

“All these forces exerted on the satellite cause it to disintegrate, which in turn means that it eventually lands in the form of a long debris trail,” said Heiner Klinkrad, head of the European Space Agency’s space debris office. “The lightweight objects fall to Earth first, similar to leaves from a tree. The really heavy objects land later, because they ultimately have to drill their way through the atmosphere.”

But engineers expect the bulk of ROSAT to survive re-entry, littering its impact point with up to 30 pieces of debris.

The 5,348-pound satellite launched from Florida on a Delta 2 rocket in 1990. ROSAT does not have an engine or propulsion system because it used reaction wheels to point its telescope toward scientific targets in the cosmos.

Up to 3,750 pounds of the satellite could reach Earth’s surface. NASA said they expected 1,200 pounds of UARS to survive re-entry.

There is a 1-in-2,000 chance someone will be struck by fragments of ROSAT on its way down, according to Germany. That equates to odds of about 1-in-14 trillion that any individual person will be hit.

The threat from UARS wasn’t as high. An analysis from NASA showed there was a 1-in-3,200 chance of a collision between a human and a piece of UARS.

The remnants of UARS fell in the remote Pacific Ocean, and ROSAT will likely also end up in the sea, but its impossible to tell where it will crash until hours before.

ROSAT launched in June 1990 on a Delta 2 rocket.

ROSAT, which stands for Roentgen Satellite, was turned off in 1999, and its altitude has gradually dropped since then from an operational orbit more than 350 miles high. The German Aerospace Center, also known as DLR by its German acronym, says the spacecraft should re-enter the atmosphere between Oct. 20 and Oct. 25.

But the margin of error in the re-entry forecast is three days, and officials likely won’t know where the satellite will come down until after it falls. Even one day before re-entry, the time of ROSAT’s demise will only be known with a precision of plus-or-minus five hours, putting entire oceans and continents in the satellite’s flight path.

“All areas under the orbit of ROSAT, which extends to 53 degrees northern and southern latitude could be affected by its re-entry,” said a posting on DLR’s website. “The bulk of the debris will impact near the ground track of the satellite.”

“It will not be possible to make any kind of reliable forecast about where the satellite will actually come down until about one or two hours before the fact,” Klinkrad said. “It will, however, be possible to predict, about one day in advance, which geographical regions will definitely not be affected.”

ROSAT’s orbit was at an average altitude of 149 miles Wednesday.

“This slow descent is due to the friction encountered by the satellite as it enters the outer fringes of Earth atmosphere, which increases the more ROSAT penetrates into our atmosphere,” Klinkrad said.

Klinkrad said the major factor affecting a satellite’s fall from orbit is solar activity. Energy unleashed from the sun causes Earth’s atmosphere to heat up and expand, generating more drag for satellites in low orbits.

Fluctuations in solar activity can quicken or slow a satellite’s re-entry. Experts initially expected ROSAT’s plunge to occur last year, but solar activity turned out to be less than predicted, delaying the re-entry until this month.

Update #6
Tue, 20 Sep 2011 02:00:29 PM MDT
As of Sept. 20, 2011, the orbit of UARS was 127 mi by 140 mi (205 km by 225 km). Re-entry is expected Sept. 23, plus or minus a day. It is still too early to predict the time and location of re-entry. Predictions will become more refined over the next two days.

NASA will post updates weekly until four days before the anticipated re-entry, then daily until about 24 hours before re-entry, and then at about 12 hours, six hours and two hours before re-entry. The updates will come from the Joint Space Operations Center of U.S. Strategic Command at Vandenberg Air Force Base, Calif., which works around the clock detecting, identifying and tracking all man-made objects in Earth orbit, including space junk.
The actual date of re-entry is difficult to predict because it depends on solar flux and the spacecraft’s orientation as its orbit decays. As re-entry draws closer, predictions on the date will become more reliable.

The risk to public safety or property is extremely small, and safety is NASA’s top priority. Since the beginning of the Space Age in the late-1950s, there have been no confirmed reports of an injury resulting from re-entering space objects. Nor is there a record of significant property damage resulting from a satellite re-entry.

If you find something you think may be a piece of UARS, do not touch it. Contact a local law enforcement official for assistance.

This composite image shows the comparative sizes of nine asteroids. Up until now, Lutetia, with a diameter of 81 miles (130 kilometers), was the largest asteroid visited by a spacecraft, which occurred during a flyby.

Vesta, which is also considered a protoplanet because it’s a large body that almost became a planet, dwarfs all other small bodies in this image, with its diameter sizing up at approximately 330 miles (530 kilometers).

The Dawn mission is managed by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., for the agency’s Science Mission Directorate in Washington. Dawn is a project of the directorate’s Discovery Program, managed by NASA’s Marshall Space Flight Center in Huntsville, Ala. UCLA is responsible for overall Dawn mission science. Orbital Sciences Corp. of Dulles, Va., designed and built the Dawn spacecraft. The framing cameras were developed and built under the leadership of the Max Planck Institute for Solar System Research in Katlenburg-Lindau, Germany. The German Aerospace Center (DLR) Institute of Planetary Research in Berlin made significant contributions in coordination with the Institute of Computer and Communication Network Engineering in Braunschweig. The framing camera project is funded by the Max Planck Society, DLR and NASA. JPL is a division of the California Institute of Technology in Pasadena.

More information about Dawn is online at http://www.nasa.gov/dawn and http://dawn.jpl.nasa.gov

PASADENA, Calif. – Scientists analyzing data from NASA’s Cassini spacecraft now have the first-ever, up-close details of a Saturn storm that is eight times the surface area of Earth.

On Dec. 5, 2010, Cassini first detected the storm that has been raging ever since. It appears at approximately 35 degrees north latitude on Saturn. Pictures from Cassini’s imaging cameras show the storm wrapping around the entire planet covering approximately 1.5 billion square miles (4 billion square kilometers).

The storm is about 500 times larger than the biggest storm previously seen by Cassini during several months from 2009 to 2010. Scientists studied the sounds of the new storm’s lightning strikes and analyzed images taken between December 2010 and February 2011. Data from Cassini’s radio and plasma wave science instrument showed the lightning flash rate as much as 10 times more frequent than during other storms monitored since Cassini’s arrival to Saturn in 2004. The data appear in a paper published this week in the journal Nature.

“Cassini shows us that Saturn is bipolar,” said Andrew Ingersoll, an author of the study and a Cassini imaging team member at the California Institute of Technology in Pasadena, Calif. “Saturn is not like Earth and Jupiter, where storms are fairly frequent. Weather on Saturn appears to hum along placidly for years and then erupt violently. I’m excited we saw weather so spectacular on our watch.”

At its most intense, the storm generated more than 10 lightning flashes per second. Even with millisecond resolution, the spacecraft’s radio and plasma wave instrument had difficulty separating individual signals during the most intense period. Scientists created a sound file from data obtained on March 15 at a slightly lower intensity period.

Cassini has detected 10 lightning storms on Saturn since the spacecraft entered the planet’s orbit and its southern hemisphere was experiencing summer, with full solar illumination not shadowed by the rings. Those storms rolled through an area in the southern hemisphere dubbed “Storm Alley.” But the sun’s illumination on the hemispheres flipped around August 2009, when the northern hemisphere began experiencing spring.

“This storm is thrilling because it shows how shifting seasons and solar illumination can dramatically stir up the weather on Saturn,” said Georg Fischer, the paper’s lead author and a radio and plasma wave science team member at the Austrian Academy of Sciences in Graz. “We have been observing storms on Saturn for almost seven years, so tracking a storm so different from the others has put us at the edge of our seats.”

The storm’s results are the first activities of a new “Saturn Storm Watch” campaign. During this effort, Cassini looks at likely storm locations on Saturn in between its scheduled observations. On the same day that the radio and plasma wave instrument detected the first lightning, Cassini’s cameras happened to be pointed at the right location as part of the campaign and captured an image of a small, bright cloud. Because analysis on that image was not completed immediately, Fischer sent out a notice to the worldwide amateur astronomy community to collect more images. A flood of amateur images helped scientists track the storm as it grew rapidly, wrapping around the planet by late January 2011.

The new details about this storm complement atmospheric disturbances described recently by scientists using Cassini’s composite infrared spectrometer and the European Southern Observatory’s Very Large Telescope. The storm is the biggest observed by spacecraft orbiting or flying by Saturn. NASA’s Hubble Space Telescope captured images in 1990 of an equally large storm.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA’s Jet Propulsion Laboratory in Pasadena manages the mission for the agency’s Science Mission Directorate in Washington. The radio and plasma wave science team is based at the University of Iowa, Iowa City, where the instrument was built. The imaging team is based at the Space Science Institute in Boulder, Colo. JPL is a division of the California Institute of Technology, Pasadena.

For images and an audio file of the storm, visit: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov .

Jia-Rui Cook 818-354-0850
Jet Propulsion Laboratory, Pasadena, Calif.
jccook@jpl.nasa.gov

Dwayne C. Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov

2011-203

Fly Your Face in Space
Space Shuttle Endeavour’s STS-134 set to launch April 29, 2011. We will be accepting image uploads until 12:00 a.m. EDT on April 30.

We are now accepting participants for STS-135. This final shuttle flight is currently targeted for launch on June 28, 2011.

Click here to learn more about this mission.

NASA Announces New Homes for Space Shuttle Orbiters After Retirement 04.12.11

After 30 years of spaceflight, more than 130 missions, and numerous science and technology firsts, NASA’s space shuttle fleet will retire and be on display at institutions across the country to inspire the next generation of explorers and engineers.

NASA Administrator Charles Bolden on Tuesday announced the facilities where four shuttle orbiters will be displayed permanently at the conclusion of the Space Shuttle Program.

Shuttle Enterprise, the first orbiter built, will move from the Smithsonian’s National Air and Space Museum Steven F. Udvar-Hazy Center in Virginia to the Intrepid Sea, Air & Space Museum in New York.
The Udvar-Hazy Center will become the new home for shuttle Discovery, which retired after completing its 39th mission in March.
Shuttle Endeavour, which is preparing for its final flight at the end of the month will go to the California Science Center in Los Angeles.
Shuttle Atlantis, which will fly the last planned shuttle mission in June, will be displayed at the Kennedy Space Center Visitor’s Complex in Florida.

“We want to thank all of the locations that expressed an interest in one of these national treasures,” Bolden said. “This was a very difficult decision, but one that was made with the American public in mind. In the end, these choices provide the greatest number of people with the best opportunity to share in the history and accomplishments of NASA’s remarkable Space Shuttle Program. These facilities we’ve chosen have a noteworthy legacy of preserving space artifacts and providing outstanding access to U.S. and international visitors.”

NASA also announced that hundreds of shuttle artifacts have been allocated to museums and education institutions.

Various shuttle simulators for the Adler Planetarium in Chicago, the Evergreen Aviation & Space Museum of McMinnville, Ore., and Texas A&M’s Aerospace Engineering Department
Full fuselage trainer for the Museum of Flight in Seattle
Nose cap assembly and crew compartment trainer for the National Museum of the U.S. Air Force at Wright-Patterson Air Force Base in Ohio
Flight deck pilot and commander seats for NASA’s Johnson Space Center in Houston
Orbital maneuvering system engines for the U.S. Space and Rocket Center of Huntsville, Ala., National Air and Space Museum in Washington, and Evergreen Aviation & Space Museum