Thursday, May 27, 2010

Swift Survey Finds 'Smoking Gun' Of Black Hole Activation

The optical counterparts of many active galactic nuclei (circled) detected by the Swift BAT Hard X-ray Survey clearly show galaxies in the process of merging. These images, taken with the 2.1-meter telescope at Kitt Peak National Observatory in Arizona, show galaxy shapes that are either physically intertwined or distorted by the gravity of nearby neighbors. These AGN were known prior to the Swift survey, but Swift has found dozens of new ones in more distant galaxies.

Data from an ongoing survey by NASA's Swift satellite have helped astronomers solve a decades-long mystery about why a small percentage of black holes emit vast amounts of energy.

Only about one percent of supermassive black holes exhibit this behavior. The new findings confirm that black holes "light up" when galaxies collide, and the data may offer insight into the future behavior of the black hole in our own Milky Way galaxy. The study will appear in the June 20 issue of The Astrophysical Journal Letters.

The intense emission from galaxy centers, or nuclei, arises near a supermassive black hole containing between a million and a billion times the sun's mass. Giving off as much as 10 billion times the sun's energy, some of these active galactic nuclei (AGN) are the most luminous objects in the universe. They include quasars and blazars.

"Theorists have shown that the violence in galaxy mergers can feed a galaxy's central black hole," said Michael Koss, the study's lead author and a graduate student at the University of Maryland in College Park. "The study elegantly explains how the black holes switched on."

Monday, May 24, 2010

Heart and Soul

The Heart and Soul nebulae are seen in this infrared mosaic from NASA's Wide-field Infrared Survey Explorer, or WISE. The image covers an area of the sky over ten times as wide as the full moon and eight times as high (5.5 x 3.9 degrees) in the constellation Cassiopeia.

Located about 6,000 light-years from Earth, the Heart and Soul nebulae form a vast star-forming complex that makes up part of the Perseus spiral arm of our Milky Way galaxy. The nebula to the left is the Heart, designated IC 1805 and named after its resemblance to a human heart. To the right is the Soul nebula, also known as the Embryo nebula, IC 1848 or W5. The Perseus arm lies further from the center of the Milky Way than the arm that contains our sun. The Heart and Soul nebulae stretch out nearly 580 light-years across, covering a small portion of the diameter of the Milky Way, which is roughly 100,000 light-years across.

The two nebulae are both massive star-making factories, marked by giant bubbles that were blown into surrounding dust by radiation and winds from the stars. WISE's infrared vision allows it to see into the cooler and dustier crevices of clouds like these, where gas and dust are just beginning to collect into new stars. These stars are less than a few million of years old -- youngsters in comparison to stars like the sun, which is nearly 5 billion years old.

Also visible near the bottom of this image are two galaxies, Maffei 1 and Maffei 2. Both galaxies contain billions of stars and, at about 10 million light-years away, are well outside our Milky Way yet relatively close compared to most galaxies. Maffei 1 is the bluish elliptical object and Maffei 2 is the spiral galaxy.

Monday, May 17, 2010

Reisman, Bowen Complete First STS-132 Spacewalk

Astronauts Garrett Reisman and Steve Bowen completed a seven hour, 25 minute spacewalk at 3:19 p.m. EDT.

The new space-to-ground antenna they installed will increase the space station's ability to conduct two-way data, voice, and video communications. They put into place a new tool platform for the Dextre robot, and Bowen prepared six batteries that will be installed during the second and third spacewalks by loosening the bolts that hold the batteries in place. The batteries weigh approximately 2,200 pounds.

Meanwhile, the space shuttle's robotic arm has successfully grappled the Mini Research Module-1 for relocation to the space station on flight day 5. It will provide additional storage space and a new docking port for Russian spacecraft.

This was the first of three STS-132 spacewalks, 237th conducted by U.S. astronauts, the second for Reisman and the fourth for Bowen. It was the 144th in support of International Space Station assembly and maintenance, totaling 900 hours, 58 minutes.

Saturday, May 15, 2010

Atlantis Lifts Off

Space shuttle Atlantis lifted off from Launch Pad 39A at NASA's Kennedy Space Center in Florida on the STS-132 mission to the International Space Station at 2:20 p.m. EDT on May 14. The third of five shuttle missions planned for 2010, this was the last planned launch for Atlantis. The Russian-built Mini Research Module-1, also known as Rassvet, or "dawn," will be delivered and it will provide additional storage space and a new docking port for Russian Soyuz and Progress spacecraft. The laboratory will be attached to the bottom port of the station's Zarya module. The mission's three spacewalks will focus on storing spare components outside the station, including six batteries, a communications antenna and parts for the Canadian Dextre robotic arm.

Tuesday, May 11, 2010

Herschel Finds a Hole in Space

The dark hole seen in the green cloud at the top of this image was likely carved out by multiple jets and blasts of radiation. The hole was originally thought to be a really dark cloud, but this new infrared picture from the Herschel space observatory and the National Optical Astronomy Observatory on Kitt Peak near Tucson, reveals that the dark spot is actually a gap in a "nest" of gas and dust containing fledgling stars. Herschel's infrared eyes are designed to see into clouds, so the fact that it saw a dark patch of space told astronomers that they were indeed looking at a hole.

The glowing, green cloud around the hole is called NGC 1999. It contains a fairly bright star, called V38O Ori, which is heating up the dust and creating the bright greenish glow. V380 Ori is a triple star system - one of these three stars appears to have launched a jet that helped clear the hole, as well as other jets and stellar radiation.

The red, filamentary glow extending through the middle of the image is a cloud of cold, dense gas and dust -- the raw material from which new stars are forming. Three new, embryonic stars can bee seen as the triangle of orangish, yellow-white spots. Bipolar jets are visible streaming out of one of these stars in blue. The dark region below and to the right of the top orange-white star of the triangle is thought to be another hole carved by jets from the star. This possible hole is not yet lit up by a star, as is the case with the hole seen above it.

Shorter-wavelength infrared light captured by the "NEWFIRM" camera at the National Optical Astronomy Observatory is colored blue, while longer-wavelength infrared light seen by the photodetector array camera and spectrometer instrument on Herschel is green and red.

Herschel is a European Space Agency cornerstone mission, with science instruments provided by consortia of European institutes and with important participation by NASA. NASA's Herschel Project Office is based at NASA's Jet Propulsion Laboratory. JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena, supports the United States astronomical community.

Saturday, May 8, 2010

GOES Exploring the Sun's Weather

The series of Geostationary Operational Environmental Satellites known as GOES provide daily satellite images of weather here on Earth, but they also provide scientists with solar data and space weather observations in geosynchronous (over a fixed location on Earth's surface) orbit. NASA has just released a four-minute educational video called "A Weather Satellite Watches the Sun" explaining the uses of space weather instruments on the GOES satellites.

"The GOES space weather instruments provide crucial data for determining the intensity of space weather events reported by forecasters using the National Oceanic and Atmospheric Administration (NOAA) Space Weather Scales," said Howard Singer, Chief Scientist, Space Weather Prediction Center, Boulder, Colo.

The four-minute video was produced by Silvia Stoyanova, a visualizer at NASA's Goddard Space Flight Center in Greenbelt, Md. The video provides information about space weather, interviews with astronaut Paul Richards, NASA GOES Deputy Project Manager Andre' Dress, NOAA's Space Weather Prediction Center Chief Scientist Howard Singer and many others to explain the importance of space weather and monitoring space weather changes.

Thursday, May 6, 2010

Herschel Gets Sneak Peak at Star Birth

The first scientific results from the Herschel infrared space observatory are revealing previously hidden details of star formation. New images show thousands of distant galaxies furiously building stars and beautiful star-forming clouds draped across our Milky Way galaxy. One picture even catches an "impossible" star in the act of formation.

Presented today during a major scientific symposium held at the European Space Agency in the Netherlands, the results challenge old ideas of star birth, and open new roads for future research. The mission is led by the European Space Agency with important participation from NASA.

"Herschel is a new eye on a part of the cosmos that has been dark and buried for a long time," said the mission's NASA project scientist, Paul Goldsmith, at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

Herschel's observation of the star-forming cloud RCW 120 has revealed an embryonic star, which appears ready to turn into one of the biggest and brightest stars in our galaxy within the next few hundred thousand years. It already contains eight to 10 times the mass of the sun and is still surrounded by an additional 2,000 solar masses of gas and dust from which it can feed further.

"This star can only grow bigger," says Annie Zavagno, Laboratoire d'Astrophysique de Marseille in France. Massive stars are rare and short-lived. To catch one during formation presents a golden opportunity to solve a long-standing paradox in astronomy. "According to our current understanding, you should not be able to form stars larger than eight solar masses," says Zavagno.

Tuesday, May 4, 2010

Station Crew Unloads Cargo, Prepares for Shuttle Docking

As aeronautics technology continues to evolve, researchers from government agencies and companies around the globe are trying to answer these questions. Developing and testing technology for planes that produce significantly less noise and have a decreased environmental impact are two of NASA's key research goals.

Flight Engineers Alexander Skvortsov and Mikhail Kornienko continue to unload and inventory the 2.6 tons of food, fuel, oxygen, propellant and supplies delivered by the ISS Progress 37. It docked at 2:30 p.m. EDT Saturday, after Commander Oleg Kotov deftly guided the cargo craft to the Pirs docking compartment using TORU, the Russian telerobotically operated rendezvous system. The manually controlled TORU system was called into play when a jet failure on the Progress forced a shutdown of the Kurs automated rendezvous system.

Saturday, May 1, 2010

Cassini Returning Enceladus Gravity Data

NASA's Cassini spacecraft successfully completed its 26-hour gravity observation at Saturn's moon Enceladus this week, sending back data scientists will use to understand the moon's interior composition and structure.

The flyby took Cassini through the water-rich plume flaring out from Enceladus' south polar region, with a closest approach of about 100 kilometers (60 miles) occurring in the late afternoon of April 27, 2010, Pacific Time, or just after midnight April 28 UTC.

A steady radio link to NASA's Deep Space Network on Earth enabled Cassini's scientists to use the radio science instrument to measure the variations in the gravitational pull of Enceladus. Analyzing the wiggles will help scientists understand whether an ocean, pond or great lake lies under the famous "tiger stripe" fractures that spew water vapor and organic particles from the south polar region.

Results from the experiment will also tell scientists if bubbles of warmer ice in the interior rise toward that region's surface like an underground lava lamp.

Radio science was prime during the flyby and controlled spacecraft pointing. The optical instruments were not pointed at Enceladus during most of the flyby, so the imaging camera obtained some more distant pictures.