NASA - Magnetar SGR 0418

NASA - Magnetar SGR 0418

THE STUDY OF SPACE WEATHER: AN EXPERIMENT AT THE SOUTH POLE

FROM: NASA 

In Antarctica in January, 2013 – the summer at the South Pole – scientists released 20 balloons, each eight stories tall, into the air to help answer an enduring space weather question: when the giant radiation belts surrounding Earth lose material, where do the extra particles actually go? This NASA-funded mission is called BARREL, for Balloon Array for Radiation belt Relativistic Electron Losses. Each balloon launched by the BARREL team floated for anywhere from three to 40 days, measuring X-rays produced by fast-moving electrons high up in the atmosphere.BARREL works hand in hand with another NASA mission called the Van Allen Probes, which travels directly through the Van Allen radiation belts. The belts wax and wane over time in response to incoming energy and material from the sun, sometimes intensifying the radiation through which satellites orbiting Earth must travel. Scientists need to understand this process better, and even provide forecasts of such space weather, in order to protect our spacecraft.  Image Credit: NASA

U.S. Department of Defense Armed with Science Update

U.S. Department of Defense Armed with Science Update

MEGA GALAXY MERGER MAKES MANY STARS

FROM: NASA, HERSCHEL SPACE OBSERVATORY
Herschel Space Observatory Finds Mega Merger of Galaxies

WASHINGTON -- A massive and rare merging of two galaxies has been spotted in images taken by the Herschel space observatory, a European Space Agency mission with important NASA participation.

Follow-up studies by several telescopes on the ground and in space, including NASA's Hubble Space Telescope and Spitzer Space Telescope, tell a tale of two faraway galaxies intertwined and furiously making stars. Eventually, the duo will settle down to form one super-giant elliptical galaxy.

The findings help explain a mystery in astronomy. Back when our universe was 3 billion to 4 billion years old, it was populated with large reddish elliptical-shaped galaxies made up of old stars. Scientists have wondered whether those galaxies built up slowly over time through the acquisitions of smaller galaxies, or formed more rapidly through powerful collisions between two large galaxies.

The new findings suggest massive mergers are responsible for the giant elliptical galaxies.

"We're looking at a younger phase in the life of these galaxies -- an adolescent burst of activity that won't last very long," said Hai Fu of the University of California at Irvine, who is lead author of a new study describing the results. The study is published in the May 22 online issue of Nature.

"These merging galaxies are bursting with new stars and completely hidden by dust," said co-author Asantha Cooray, also of the University of California at Irvine. "Without Herschel's far-infrared detectors, we wouldn't have been able to see through the dust to the action taking place behind."

Herschel, which operated for almost four years, was designed to see the longest-wavelength infrared light. As expected, it recently ran out of the liquid coolant needed to chill its delicate infrared instruments. While its mission in space is over, astronomers still are scrutinizing the data, and further discoveries are expected.

In the new study, Herschel was used to spot the colliding galaxies, called HXMM01, located about 11 billion light-years from Earth, during a time when our universe was about 3 billion years old. At first, astronomers thought the two galaxies were just warped, mirror images of one galaxy. Such lensed galaxies are fairly common in astronomy and occur when the gravity from a foreground galaxy bends the light from a more distant object. After a thorough investigation, the team realized they were actually looking at a massive galaxy merger.

Follow-up characterization revealed the duo is churning out the equivalent of 2,000 stars a year. By comparison, our Milky Way hatches about two to three stars a year. The total number of stars in both colliding galaxies averages out to about 400 billion.

Mergers are fairly common in the cosmos, but this particular event is more unusual because of the prolific amounts of gas and star formation, and the sheer size of the merger at such a distant epoch.

The results go against the more popular model explaining how the biggest galaxies arise: through minor acquisitions of small galaxies. Instead, mega smash-ups may be doing the job.

U.S. Department of Defense Armed with Science Update

U.S. Department of Defense Armed with Science Update

NASA - California Governor Brown Meets Scientists at NASA Ames

NASA - California Governor Brown Meets Scientists at NASA Ames

Una fusión excepcional desvela los secretos de la evolución de las galaxias

Una fusión excepcional desvela los secretos de la evolución de las galaxias

U.S. Department of Defense Armed with Science Update

U.S. Department of Defense Armed with Science Update

Immagine EO della settimana: Acque limpide nei laghi canadesi

Immagine EO della settimana: Acque limpide nei laghi canadesi

Proba-V opent ogen

Proba-V opent ogen

IMMENSE POWER GENERATED BY SUPERMASSIVE BLACK HOLE

FROM: NASA

This composite image of a galaxy illustrates how the intense gravity of a supermassive black hole can be tapped to generate immense power. The image contains X-ray data from NASA's Chandra X-ray Observatory (blue), optical light obtained with the Hubble Space Telescope (gold) and radio waves from the NSF’s Very Large Array (pink).

This multi-wavelength view shows 4C+29.30, a galaxy located some 850 million light years from Earth. The radio emission comes from two jets of particles that are speeding at millions of miles per hour away from a supermassive black hole at the center of the galaxy. The estimated mass of the black hole is about 100 million times the mass of our Sun. The ends of the jets show larger areas of radio emission located outside the galaxy.

The X-ray data show a different aspect of this galaxy, tracing the location of hot gas. The bright X-rays in the center of the image mark a pool of million-degree gas around the black hole. Some of this material may eventually be consumed by the black hole, and the magnetized, whirlpool of gas near the black hole could in turn, trigger more output to the radio jet.

Most of the low-energy X-rays from the vicinity of the black hole are absorbed by dust and gas, probably in the shape of a giant doughnut around the black hole. This doughnut, or torus blocks all the optical light produced near the black hole, so astronomers refer to this type of source as a hidden or buried black hole. The optical light seen in the image is from the stars in the galaxy.

The bright spots in X-ray and radio emission on the outer edges of the galaxy, near the ends of the jets, are caused by extremely high energy electrons following curved paths around magnetic field lines. They show where a jet generated by the black hole has plowed into clumps of material in the galaxy (mouse over the image for the location of these bright spots). Much of the energy of the jet goes into heating the gas in these clumps, and some of it goes into dragging cool gas along the direction of the jet. Both the heating and the dragging can limit the fuel supply for the supermassive black hole, leading to temporary starvation and stopping its growth. This feedback process is thought to cause the observed correlation between the mass of the supermassive black hole and the combined mass of the stars in the central region or bulge or a galaxy.

These results were reported in two different papers. The first, which concentrated on the effects of the jets on the galaxy, is available online and was published in the May 10, 2012 issue of The Astrophysical Journal. It is led by Aneta Siemiginowska from the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, MA and the co-authors are Łukasz Stawarz, from the Institute of Space and Astronautical Science in Yoshinodai, Japan; Teddy Cheung from the National Academy of Sciences in Washington, DC; Thomas Aldcroft from CfA; Jill Bechtold from University of Arizona in Tucson, AZ; Douglas Burke from CfA; Daniel Evans from CfA; Joanna Holt from Leiden University in Leiden, The Netherlands; Marek Jamrozy from Jagiellonian University in Krakow, Poland; and Giulia Migliori from CfA. The second, which concentrated on the supermassive black hole, is available online and was published in the October 20, 2012 issue of The Astrophysical Journal. It is led by Malgorzata Sobolewska from CfA, and the co-authors are Aneta Siemiginowska, Giulia Migliori, Łukasz Stawarz, Marek Jamrozy, Daniel Evans, and Teddy Cheung.

NASA's Marshall Space Flight Center in Huntsville, Ala., manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory controls Chandra's science and flight operations from Cambridge, Mass.

Credits: X-ray: NASA/CXC/SAO/A. Siemiginowska et al; Optical: NASA/STScI; Radio: NSF/NRAO/VLA

NASA - NASA's Google Hangout Connects Space Station, "Star Trek Into Darkness" Crews

NASA - NASA's Google Hangout Connects Space Station, "Star Trek Into Darkness" Crews

First new Galileo satellite arrives at ESA for space testing

First new Galileo satellite arrives at ESA for space testing

U.S. Department of Defense Armed with Science Update

U.S. Department of Defense Armed with Science Update

U.S. Department of Defense Armed with Science Update

U.S. Department of Defense Armed with Science Update