Sunday, December 30, 2012

Spiral Galaxy NGC 3627

0 comments

The spiral galaxy NGC 3627 is located about 30 million light years from Earth. This composite image includes X-ray data from NASA's Chandra X-ray Observatory (blue), infrared data from the Spitzer Space Telescope (red), and optical data from the Hubble Space Telescope and the Very Large Telescope (yellow). The inset shows the central region, which contains a bright X-ray source that is likely powered by material falling onto a supermassive black hole.

A search using archival data from previous Chandra observations of a sample of 62 nearby galaxies has shown that 37 of the galaxies, including NGC 3627, contain X-ray sources in their centers. Most of these sources are likely powered by central supermassive black holes. The survey, which also used data from the Spitzer Infrared Nearby Galaxy Survey, found that seven of the 37 sources are new supermassive black hole candidates.

Confirming previous Chandra results, this study finds the fraction of galaxies found to be hosting supermassive black holes is much higher than found with optical searches. This shows the ability of X-ray observations to find black holes in galaxies where relatively low-level black hole activity has either been hidden by obscuring material or washed out by the bright optical light of the galaxy. 

Wednesday, December 26, 2012

New Mars Photo Christens Deep-Space Antenna

0 comments
                                    


The Malargüe antenna is one of three deep-space tracking installations that make up ESA's Estrack system. Construction of the 600-ton antenna began in 2010 and was completed this year. The site's nearly 115-foot (35-meter) dish is designed to serve as both a ground station for satellites in Earth orbit and spacecraft exploring other destinations in the solar system. The two other installations of the Estrack system are located in New Norcia, Australia, and Cebreros, Spain.
"With the Malargüe station, ESA becomes only the second space agency in the world to provide all-sky coverage for deep-space missions," ESA's Director-General Jean-Jacques Dordain said in a statement. The other space agency with the capability is the U.S.-based NASA, which operates its own Deep Space Network of ground stations.
ESA's Mars Express spacecraft has been orbiting the Red Planet since December 2003. It is currently in the midst of an extended mission that runs through 2014.

Sunday, December 23, 2012

NASA CAPTURES SOLSTICE SOLAR PORTRAIT

0 comments

At 11:12 UT (6:12 a.m. EST), the world didn't end (as far as I can tell), but it was a significant time none-the-less. That was the exact minute of the Winter Solstice in the Northern Hemisphere (or the Summer Solstice in the Southern Hemisphere) -- when the daylight hours are shortest and the sun reaches its most southern position in the sky at noon.

The ever-watchful NASA Solar Dynamics Observatory (SDO) captured the time of solstice from orbit. Although the SDO is always imaging the sun through a multitude of filters, this is a great excuse to showcase the fantastic beauty of our nearest star, while putting all the doomsday nonsense behind us.
The sun didn't unleash a killer solar flare or devastating coronal mass ejection, but it is undergoing a fascinating period in its solar cycle.

As can be seen from the SDO image above, the solar magnetic field is twisted and warped, channeling million-degree plasma high into the sun's atmosphere in the form of beautiful coronal loops. This is all because the sun is fast approaching "solar maximum" -- an exciting time when the sun's magnetic field is most stressed.

We can expect a lot more flares and CMEs from now and through 2013; although these events can damage satellites and threaten power supplies, they're not the flares described in doomsday myth.
So sit back, and enjoy some solar science and spectacular views of our star as it enters the most dramatic time of its cycle.

Monday, March 12, 2012

Citizen Scientists Reveal a Bubbly Milky Way

0 comments
A team of volunteers has pored over observations from NASA's Spitzer Space Telescope and discovered more than 5,000 "bubbles" in the disk of our Milky Way galaxy. Young, hot stars blow these bubbles into surrounding gas and dust, indicating areas of brand new star formation.

Upwards of 35,000 "citizen scientists" sifted through the Spitzer infrared data as part of the online Milky Way Project to find these telltale bubbles. The volunteers have turned up 10 times as many bubbles as previous surveys so far.

"These findings make us suspect that the Milky Way is a much more active star-forming galaxy than previously thought," said Eli Bressert, an astrophysics doctoral student at the European Southern Observatory, based in Germany, and the University of Exeter, England, and co-author of a paper submitted to the Monthly Notices of the Royal Astronomical Society.

"The Milky Way's disk is like champagne with bubbles all over the place," he said.

Computer programs struggle at identifying the cosmic bubbles. But human eyes and minds do an excellent job of noticing the wispy arcs of partially broken rings and the circles-within-circles of overlapping bubbles. The Milky Way Project taps into the "wisdom of crowds" by requiring that at least five users flag a potential bubble before its inclusion in the new catalog. Volunteers mark any candidate bubbles in the infrared Spitzer images with a sophisticated drawing tool before proceeding to scour another image.

"The Milky Way Project is an attempt to take the vast and beautiful data from Spitzer and make extracting the information a fun, online, public endeavor," said Robert Simpson, a postdoctoral researcher in astronomy at Oxford University, England, principal investigator of the Milky Way Project and lead author of the paper.

The data come from the Spitzer Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) and Multiband Imaging Photometer for Spitzer Galactic (MIPSGAL) surveys. These datasets cover a narrow, wide strip of the sky measuring 130 degrees wide and just two degrees tall. From a stargazer's perspective, a two-degree strip is about the width of your index finger held at arm's length, and your arms opened to the sky span about 130 degrees. The surveys peer through the Milky Way's disk and right into the galaxy's heart.

The bubbles tagged by the volunteers vary in size and shape, both with distance and due to local gas cloud variations. The results will help astronomers better identify star formation across the galaxy. One topic under investigation is triggered star formation, in which the bubble-blowing birth of massive stars compresses nearby gas that then collapses to create further fresh stars.

Tuesday, March 06, 2012

Proposed Mars Mission Has New Name

0 comments
A proposed Discovery mission concept led by NASA's Jet Propulsion Laboratory, Pasadena, Calif., to investigate the formation and evolution of terrestrial planets by studying the deep interior of Mars now has a new name, InSight.

InSight stands for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport and is a partnership involving JPL, Lockheed Martin Space Systems, the French Space Agency (CNES), the German Aerospace Center (DLR), and other NASA centers. The previous name for the proposal was GEMS (GEophysical Monitoring Station). NASA requested that name be reserved for an astrophysics mission known as the Gravity and Extreme Magnetism Small Explorer, which was already in development.

"We chose the name InSight because we would literally peer into the interior of Mars to map out its structure," said JPL's Bruce Banerdt, the principal investigator. "With our geophysical instruments we will be able to see right through to the center of Mars, and will be able to map out how deeply the crust extends as well as the size of the core."

InSight is one of three missions vying to be selected for flight in the Discovery Program, a series of NASA missions to understand the solar system by exploring planets, moons, and small bodies such as comets and asteroids. All three mission teams are required to submit concept study reports to NASA on March 19.

For more information, visit http://insight.jpl.nasa.gov/ .

Friday, February 24, 2012

NASA Satellite Finds Earth's Clouds are Getting Lower

0 comments
Earth's clouds got a little lower -- about one percent on average -- during the first decade of this century, finds a new NASA-funded university study based on NASA satellite data. The results have potential implications for future global climate.

Scientists at the University of Auckland in New Zealand analyzed the first 10 years of global cloud-top height measurements (from March 2000 to February 2010) from the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA's Terra spacecraft. The study, published recently in the journal Geophysical Research Letters, revealed an overall trend of decreasing cloud height. Global average cloud height declined by around one percent over the decade, or by around 100 to 130 feet (30 to 40 meters). Most of the reduction was due to fewer clouds occurring at very high altitudes.

Lead researcher Roger Davies said that while the record is too short to be definitive, it provides a hint that something quite important might be going on. Longer-term monitoring will be required to determine the significance of the observation for global temperatures.

A consistent reduction in cloud height would allow Earth to cool to space more efficiently, reducing the surface temperature of the planet and potentially slowing the effects of global warming. This may represent a "negative feedback" mechanism - a change caused by global warming that works to counteract it. "We don't know exactly what causes the cloud heights to lower," says Davies. "But it must be due to a change in the circulation patterns that give rise to cloud formation at high altitude."

NASA's Terra spacecraft is scheduled to continue gathering data through the remainder of this decade. Scientists will continue to monitor the MISR data closely to see if this trend continues.

For more information, visit: http://www.auckland.ac.nz/uoa/home/news/template/news_item.jsp?cid=466683 .

Tuesday, February 14, 2012

NASA's Galaxy Evolution Explorer in Standby Mode

0 comments
NASA's Galaxy Evolution Explorer, or Galex, was placed in standby mode today as engineers prepare to end mission operations, nearly nine years after the telescope's launch. The spacecraft is scheduled to be decommissioned -- taken out of service -- later this year. The mission extensively mapped large portions of the sky with sharp ultraviolet vision, cataloguing millions of galaxies spanning 10 billion years of cosmic time.

The Galaxy Evolution Explorer launched into space from a Pegasus XL rocket in April of 2003. Since completing its prime mission in the fall of 2007, the mission was extended to continue its census of stars and galaxies.

The mission's science highlights include the discovery of a gigantic comet-like tail behind a speeding star, rings of new stars around old galaxies, and "teenager" galaxies, which help to explain how galaxies evolve. The observatory also helped confirm the existence of the mysterious substance or force known as dark energy, and even caught a black hole devouring a star.

The California Institute of Technology, Pasadena, Calif., leads the Galaxy Evolution Explorer mission and is responsible for science operations and data analysis. NASA's Jet Propulsion Laboratory, also in Pasadena, manages the mission and built the science instrument. The mission was developed under NASA's Explorers Program, managed by the Goddard Space Flight Center, Greenbelt, Md. Researchers sponsored by Yonsei University in South Korea and the Centre National d'Etudes Spatiales (CNES) in France collaborated on this mission. Caltech manages JPL for NASA.

Graphics and additional information about the Galaxy Evolution Explorer are online at http://www.nasa.gov/galex/ and http://www.galex.caltech.edu/ .