Fastest Rotating Star Found in Neighboring Galaxy

This artist's concept pictures the fastest rotating star found to date. The massive, bright young star, called VFTS 102, rotates at a million miles per hour, or 100 times faster than our sun does. Centrifugal forces from this dizzying spin rate have flattened the star into an oblate shape and spun off a disk of hot plasma, seen edge on in this view from a hypothetical planet. The star may have "spun up" by accreting material from a binary companion star. The rapidly evolving companion later exploded as a supernova. The whirling star lies 160,000 light-years away in the Large Magellanic Cloud, a satellite galaxy of the Milky Way.

Source : NASA
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NASA Discovers First Earth-size Planets beyond Our Solar System

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 continues 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.

Source : NASA

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New Expedition 30 Crew Members Launch to Station

Expedition 30 Flight Engineers Don Pettit, Oleg Kononenko and Andre Kuipers launched at 8:16 a.m. EST on Wednesday, Dec. 21 (7:16 p.m. local time) from the Baikonur Cosmodrome in Kazakhstan. The three new International Space Station crew members launched in their Soyuz TMA-03M spacecraft beginning a two-day trip to the orbiting outpost.

They are set to dock to the station's Rassvet mini-research module about 10:22 a.m. on Friday, Dec. 23. Expedition 30 Commander Dan Burbank and Flight Engineers Anton Shkaplerov and Anatoly Ivanishin will welcome their new crewmates aboard the station a little while later when they open the hatches about 1 p.m.

Pettit, Kononenko and Kuipers are scheduled to live and work aboard the orbiting laboratory until May. They will become members of the Expedition 31 crew under the command of Kononenko when Burbank, Shkaplerov and Ivanishin undock in their Soyuz TMA-22 spacecraft in March.

Source : NASA

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NASA Telescopes Help Find Rare Galaxy at Dawn of Time

Astronomers using NASA's Spitzer and Hubble space telescopes have discovered that one of the most distant galaxies known is churning out stars at a shockingly high rate. The blob-shaped galaxy, called GN-108036, is the brightest galaxy found to date at such great distances.

The galaxy, which was discovered and confirmed using ground-based telescopes, is 12.9 billion light-years away. Data from Spitzer and Hubble were used to measure the galaxy's high star production rate, equivalent to about 100 suns per year. For reference, our Milky Way galaxy is about five times larger and 100 times more massive than GN-108036, but makes roughly 30 times fewer stars per year.

"The discovery is surprising because previous surveys had not found galaxies this bright so early in the history of the universe," said Mark Dickinson of the National Optical Astronomy Observatory in Tucson, Ariz. "Perhaps those surveys were just too small to find galaxies like GN-108036. It may be a special, rare object that we just happened to catch during an extreme burst of star formation."

The international team of astronomers, led by Masami Ouchi of the University of Tokyo, Japan, first identified the remote galaxy after scanning a large patch of sky with the Subaru Telescope atop Mauna Kea in Hawaii. Its great distance was then carefully confirmed with the W.M. Keck Observatory, also on Mauna Kea.

"We checked our results on three different occasions over two years, and each time confirmed the previous measurement," said Yoshiaki Ono of the University of Tokyo, lead author of a new paper reporting the findings in the Astrophysical Journal.

GN-108036 lies near the very beginning of time itself, a mere 750 million years after our universe was created 13.7 billion years ago in an explosive "Big Bang." Its light has taken 12.9 billion years to reach us, so we are seeing it as it existed in the very distant past.

Astronomers refer to the object's distance by a number called its "redshift," which relates to how much its light has stretched to longer, redder wavelengths due to the expansion of the universe. Objects with larger redshifts are farther away and are seen further back in time. GN-108036 has a redshift of 7.2. Only a handful of galaxies have confirmed redshifts greater than 7, and only two of these have been reported to be more distant than GN-108036.

Infrared observations from Spitzer and Hubble were crucial for measuring the galaxy's star-formation activity. Astronomers were surprised to see such a large burst of star formation because the galaxy is so small and from such an early cosmic era. Back when galaxies were first forming, in the first few hundreds of millions of years after the Big Bang, they were much smaller than they are today, having yet to bulk up in mass.

During this epoch, as the universe expanded and cooled after its explosive start, hydrogen atoms permeating the cosmos formed a thick fog that was opaque to ultraviolet light. This period, before the first stars and galaxies had formed and illuminated the universe, is referred to as the "dark ages." The era came to an end when light from the earliest galaxies burned through, or "ionized," the opaque gas, causing it to become transparent. Galaxies similar to GN-108036 may have played an important role in this event.

"The high rate of star formation found for GN-108036 implies that it was rapidly building up its mass some 750 million years after the Big Bang, when the universe was only about five percent of its present age," said Bahram Mobasher, a team member from the University of California, Riverside. "This was therefore a likely ancestor of massive and evolved galaxies seen today."

 Source : NASA

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NASA 'Smart SPHERES' Tested Successfully on International Space Station

In November, a free-flying robot on the International Space Station successfully gathered and delivered motion data to its astronaut handler for the first time via a new smartphone controller.

The Human Exploration Telerobotics project, one of NASA's new, high-value Technology Demonstration Missions, equipped the compact, free-flying satellites -- known as Synchronized Position Hold, Engage, Reorient Experimental Satellites, or SPHERES -- with a Samsung Nexus S™ handset that features Google’s open-source Android™ platform.

Each volleyball-sized SPHERES has its own onboard power, propulsion, computing and navigational software. Adding the smartphone transforms the satellite into a free-flying robot, or "Smart SPHERES" -- complete with a compact, low-power, low-cost embedded computer and built-in cameras and sensors to enhance and expand robotic operations.

Minor modifications were made to the smartphones, including removing the GSM cellular communications chip to avoid interference with station electronics, and replacing the standard lithium-ion battery with AA alkaline batteries. Otherwise, the smartphone is identical to the off-the-shelf consumer device. 

The ongoing experiment demonstrates how the Smart SPHERES can serve as remotely operated assistants for astronauts in space. In coming months, these compact assistants will conduct interior station surveys and inspections, capturing mobile camera images and video. NASA also plans to simulate external free-flight excursions and in time will test whether the robots can handle other, more challenging tasks.

"The tests that we are conducting with Smart SPHERES will help NASA make better use of robots as assistants to and versatile support for human explorers -- in Earth orbit or on long missions to other worlds and new destinations," said Terry Fong, project manager of the Human Exploration Telerobotics project and Director of the Intelligent Robotics Group at NASA's Ames Research Center in Moffett Field, Calif.

The Nexus S phone is the first commercial smartphone certified by NASA for use on the space station. Each smartphone is connected to a SPHERES free-flyer via a cable. A wireless network connection (Wi-Fi) to the space station's computers provides the data path to the ground. NASA anticipates using other types of smartphones on the station in the future.

Source : NASA

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A 'Rose' Made of Galaxies

In celebration of the twenty-firstt anniversary of the Hubble Space Telescope's deployment in April 2011, astronomers at the Space Telescope Science Institute pointed Hubble's eye to an especially photogenic group of interacting galaxies called Arp 273.

The larger of the spiral galaxies, known as UGC 1810, has a disk that is tidally distorted into a rose-like shape by the gravitational tidal pull of the companion galaxy below it, known as UGC 1813. A swath of blue jewels across the top is the combined light from clusters of intensely bright and hot young blue stars. These massive stars glow fiercely in ultraviolet light.

The smaller, nearly edge-on companion shows distinct signs of intense star formation at its nucleus, perhaps triggered by the encounter with the companion galaxy.

A series of uncommon spiral patterns in the large galaxy is a tell-tale sign of interaction. The large, outer arm appears partially as a ring, a feature seen when interacting galaxies actually pass through one another. This suggests that the smaller companion actually dived deep, but off-center, through UGC 1810. The inner set of spiral arms is highly warped out of the plane with one of the arms going behind the bulge and coming back out the other side. How these two spiral patterns connect is still not precisely known.

The interaction was imaged on Dec. 17, 2010, with Hubble's Wide Field Camera 3 (WFC3).

This Hubble image is a composite of data taken with three separate filters on WFC3 that allow a broad range of wavelengths covering the ultraviolet, blue and red portions of the spectrum.

Source NASA

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NASA Mars-Bound Rover Begins Research in Space

NASA's car-sized Curiosity rover has begun monitoring space radiation during its 8-month trip from Earth to Mars. The research will aid in planning for future human missions to the Red Planet.

Curiosity launched on Nov. 26 from Cape Canaveral, Fla., aboard the Mars Science Laboratory. The rover carries an instrument called the Radiation Assessment Detector (RAD) that monitors high-energy atomic and subatomic particles from the sun, distant supernovas and other sources.

   These particles constitute radiation that could be harmful to any microbes or astronauts in space or on Mars. The rover also will monitor radiation on the surface of Mars after its August 2012 landing.

"RAD is serving as a proxy for an astronaut inside a spacecraft on the way to Mars," said Don Hassler, RAD's principal investigator from the Southwest Research Institute in Boulder, Colo. "The instrument is deep inside the spacecraft, the way an astronaut would be. Understanding the effects of the spacecraft on the radiation field will be valuable in designing craft for astronauts to travel to Mars."

Previous monitoring of energetic-particle radiation in space has used instruments at or near the surface of various spacecraft. The RAD instrument is on the rover inside the spacecraft and shielded by other components of Mars Science Laboratory, including the aeroshell that will protect the rover during descent through the upper atmosphere of Mars.

 Spacecraft structures, while providing  shielding, also can contribute to secondary   particles generated when high-energy particles strike the spacecraft. In some circumstances, secondary particles could be more hazardous than primary ones.

These first measurements mark the start of the science return from a mission that will use 10 instruments on Curiosity to assess whether Mars' Gale Crater could be or has been favorable for microbial life.

"While Curiosity will not look for signs of life on Mars, what it might find could be a game-changer about the origin and evolution of life on Earth and elsewhere in the universe," said Doug McCuistion, director of the Mars Exploration Program at NASA Headquarters in Washington. "One thing is certain: The rover's discoveries will provide critical data that will impact human and robotic planning and research for decades."

Source : NASA

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