Author Topic: NASA - Chandra X-Ray - updates  (Read 44481 times)

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NASA - Chandra X-Ray - updates
« on: 05/07/2008 04:39 pm »
MEDIA ADVISORY: M08-089

NASA TO ANNOUNCE SUCCESS OF LONG GALACTIC HUNT

WASHINGTON -- NASA has scheduled a media teleconference Wednesday, May
14, at 1 p.m. EDT, to announce the discovery of an object in our
Galaxy astronomers have been hunting for more than 50 years. This
finding was made by combining data from NASA's Chandra X-ray
Observatory with ground-based observations.

To participate in the teleconference, reporters must contact the
Chandra Press Office at 617-496-7998 or e-mail
[email protected]. Live audio of the teleconference will be
streamed online at:

http://www.nasa.gov/newsaudio

A video file about the discovery will air on NASA Television on May
14. NASA TV is carried on an MPEG-2 digital signal accessed via
satellite AMC-6, at 72 degrees west longitude, transponder 17C, 4040
MHz, vertical polarization. NASA TV is available in Alaska and Hawaii
on AMC-7 at 137 degrees west longitude, transponder 18C, at 4060 MHz,
horizontal polarization.

For information about NASA's Chandra X-Ray Observatory on the Web,
visit:

http://www.nasa.gov/chandra
Jacques :-)

Online jacqmans

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Re: NASA - Chandra X-Ray - updates
« Reply #1 on: 07/23/2009 02:21 pm »
RELEASE: 09-171

NASA CELEBRATES CHANDRA X-RAY OBSERVATORY'S 10TH ANNIVERSARY

WASHINGTON -- Ten years ago, on July 23, 1999, NASA's Chandra X-ray
Observatory was launched aboard the space shuttle Columbia and
deployed into orbit. Chandra has doubled its original five-year
mission, ushering in an unprecedented decade of discovery for the
high-energy universe.

With its unrivaled ability to create high-resolution X- ray images,
Chandra has enabled astronomers to investigate phenomena as diverse
as comets, black holes, dark matter and dark energy.

"Chandra's discoveries are truly astonishing and have made dramatic
changes to our understanding of the universe and its constituents,"
said Martin Weisskopf, Chandra project scientist at NASA's Marshall
Space Flight Center in Huntsville, Ala.

The science that has been generated by Chandra -- both on its own and
in conjunction with other telescopes in space and on the ground --
has had a widespread, transformative impact on 21st century
astrophysics. Chandra has provided the strongest evidence yet that
dark matter must exist. It has independently confirmed the existence
of dark energy and made spectacular images of titanic explosions
produced by matter swirling toward supermassive black holes.

To commemorate the 10th anniversary of Chandra, three new versions of
classic Chandra images will be released during the next three months.
These images, the first of which is available Thursday, provide new
data and a more complete view of objects that Chandra observed in
earlier stages of its mission. The image being released today is of
E0102-72, the spectacular remains of an exploded star.

"The Great Observatories program -- of which Chandra is a major part
-- shows how astronomers need as many tools as possible to tackle the
big questions out there," said Ed Weiler, associate administrator of
NASA's Science Mission Directorate at NASA Headquarters in
Washington. NASA's other "Great Observatories" are the Hubble Space
Telescope, Compton Gamma-Ray Observatory and Spitzer Space Telescope.


The next image will be released in August to highlight the anniversary
of when Chandra opened up for the first time and gathered light on
its detectors. The third image will be released during "Chandra's
First Decade of Discovery" symposium in Boston, which begins Sept.
22.

"I am extremely proud of the tremendous team of people who worked so
hard to make Chandra a success," said Harvey Tananbaum, director of
the Chandra X-ray Center at the Smithsonian Astrophysical Observatory
in Cambridge, Mass. "It has taken partners at NASA, industry and
academia to make Chandra the crown jewel of high-energy
astrophysics."

Tananbaum and Nobel Prize winner Riccardo Giacconi originally proposed
Chandra to NASA in 1976. Unlike the Hubble Space Telescope, Chandra
is in a highly elliptical orbit that takes it almost one third of the
way to the moon, and was not designed to be serviced after it was
deployed.

Marshall manages the Chandra program for NASA's Science Mission
Directorate. The Smithsonian Astrophysical Observatory controls
science and flight operations from the Chandra X-ray Center.

A list of Chandra's major scientific highlights is available at:

http://chandra.harvard.edu/ten/


To view new images from Chandra and learn more about the mission
visit:

http://chandra.nasa.gov

Jacques :-)

Online jacqmans

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Re: NASA - Chandra X-Ray - updates
« Reply #2 on: 01/01/2010 10:35 am »
CONTRACT RELEASE: C09-060

NASA EXTENDS CHANDRA SCIENCE AND OPERATIONS SUPPORT CONTRACT

WASHINGTON -- NASA has extended a contract with the Smithsonian
Astrophysical Observatory in Cambridge, Mass., to provide science and
operational support for the Chandra X-ray Observatory, a powerful
tool used to better understand the structure and evolution of the
universe.

The contract extension with the Smithsonian Astrophysical Observatory
provides continued science and operations support to Chandra. This
approximately $172 million modification brings the total value of the
contract to approximately $545 million for the base effort. The base
effort period of performance will continue through Sept. 30, 2013,
except for the work associated with the administration of scientific
research grants, which will extend through Feb. 28, 2016. The
contract type is cost reimbursement with no fee.

In addition to the base effort, the contract includes two options for
three years each to extend the period of performance for an
additional six years. Option 1 is priced at approximately $177
million and Option 2 at approximately $191 million, for a total
possible contract value of about $913 million.

The contract covers mission operations and data analysis, which
includes observatory operations, science data processing and
astronomer support. The operations tasks include monitoring the
health and status of the observatory and developing and uplinking the
observation sequences during Chandra's communication coverage
periods. The science data processing tasks include the competitive
selection, planning and coordination of science observations and
processing and delivery of the resulting scientific data.

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

For more information about NASA visit:

http://www.nasa.gov


For more information about the Chandra X-ray Observatory visit:

http://chandra.nasa.gov

Jacques :-)

Offline robertross

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Re: NASA - Chandra X-Ray - updates
« Reply #3 on: 01/01/2010 05:16 pm »
Excellent news, thanks.

Online jacqmans

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Re: NASA - Chandra X-Ray - updates
« Reply #4 on: 02/17/2010 09:01 pm »
RELEASE: 10-042

NASA'S CHANDRA REVEALS ORIGIN OF KEY COSMIC EXPLOSIONS

WASHINGTON -- New findings from NASA's Chandra X-ray Observatory have
provided a major advance in understanding a type of supernova
critical for studying the dark energy that astronomers think pervades
the universe. The results show mergers of two dense stellar remnants
are the likely cause of many of the supernovae that have been used to
measure the accelerated expansion of the universe.

These supernovae, called Type 1a, serve as cosmic mile markers to
measure expansion of the universe because they can be seen at large
distances, and they follow a reliable pattern of brightness. However,
until now, scientists have been unsure what actually causes the
explosions.

"These are such critical objects in understanding the universe," said
Marat Gilfanov of the Max Planck Institute for Astrophysics in
Germany and lead author of the study that appears in the Feb. 18
edition of the journal Nature. "It was a major embarrassment that we
did not know how they worked. Now we are beginning to understand what
lights the fuse of these explosions."

Most scientists agree a Type 1a supernova occurs when a white dwarf
star -- a collapsed remnant of an elderly star -- exceeds its weight
limit, becomes unstable and explodes. Scientists have identified two
main possibilities for pushing the white dwarf over the edge: two
white dwarfs merging or accretion, a process in which the white dwarf
pulls material from a sun-like companion star until it exceeds its
weight limit.

"Our results suggest the supernovae in the galaxies we studied almost
all come from two white dwarfs merging," said co-author Akos Bogdan,
also of Max Planck. "This is probably not what many astronomers would
expect."

The difference between these two scenarios may have implications for
how these supernovae can be used as "standard candles" -- objects of
a known brightness -- to track vast cosmic distances. Because white
dwarfs can come in a range of masses, the merger of two could result
in explosions that vary somewhat in brightness.

Because these two scenarios would generate different amounts of X-ray
emission, Gilfanov and Bogdan used Chandra to observe five nearby
elliptical galaxies and the central region of the Andromeda galaxy. A
Type 1a supernova caused by accreting material produces significant
X-ray emission prior to the explosion. A supernova from a merger of
two white dwarfs, on the other hand, would create significantly less
X-ray emission than the accretion scenario.

The scientists found the observed X-ray emission was a factor of 30 to
50 times smaller than expected from the accretion scenario,
effectively ruling it out. This implies that white dwarf mergers
dominate in these galaxies.

An open question remains whether these white dwarf mergers are the
primary catalyst for Type 1a supernovae in spiral galaxies. Further
studies are required to know if supernovae in spiral galaxies are
caused by mergers or a mixture of the two processes. Another
intriguing consequence of this result is that a pair of white dwarfs
is relatively hard to spot, even with the best telescopes.

"To many astrophysicists, the merger scenario seemed to be less likely
because too few double-white-dwarf systems appeared to exist," said
Gilfanov. "Now this path to supernovae will have to be investigated
in more detail."

In addition to the X-rays observed with Chandra, other data critical
for this result came from NASA's Spitzer Space Telescope and the
ground-based, infrared Two Micron All Sky Survey. The infrared
brightness of the galaxies allowed the team to estimate how many
supernovae should occur.

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.

More information, including images and other multimedia, can be found
at:

http://chandra.nasa.gov


and


http://chandra.harvard.edu


-end-
Jacques :-)

Offline Space Pete

Re: NASA - Chandra X-Ray - updates
« Reply #5 on: 07/22/2010 09:23 pm »
Black Hole Jerked Around Twice
07.21.10
 
Scientists have found evidence that a giant black hole has been jerked around twice, causing its spin axis to point in a different direction from before. This discovery, made with new data from NASA's Chandra X- ray Observatory, might explain several mysterious-looking objects found throughout the Universe.

The axis of the spinning black hole is thought to have moved, but not the black hole itself, so this result differs from recently published work on recoiling black holes.

"We think this is the best evidence ever seen for a black hole having been jerked around like this," said Edmund Hodges-Kluck of the University of Maryland. "We're not exactly sure what caused this behavior, but it was probably triggered by a collision between two galaxies."

A team of astronomers used Chandra for a long observation of a galaxy known as 4C +00.58, which is located about 780 million light years from Earth. Like most galaxies, 4C +00.58 contains a supermassive black hole at its center, but this one is actively pulling in copious quantities of gas. Gas swirling toward the black hole forms a disk around the black hole. Twisted magnetic fields in the disk generate strong electromagnetic forces that propel some of the gas away from the disk at high speed, producing radio jets.

A radio image of this galaxy shows a bright pair of jets pointing from left to right and a fainter, more distant line of radio emission running in a different direction. More specifically, 4C +00.58 belongs to a class of "X-shaped" galaxies, so called because of the outline of their radio emission.

The new Chandra data have allowed astronomers to determine what may be happening in this system, and perhaps in others like it. The X-ray image reveals four different cavities around the black hole. These cavities come in pairs: one in the top-right and bottom-left, and another in the top-left and bottom-right.

When combined with the orientation of the radio jets, the complicated geometry revealed in the Chandra image may tell the story of what happened to this supermassive black hole and the galaxy it inhabits.

"We think that this black hole has quite a history," said Christopher Reynolds of the University of Maryland in College Park. "Not once, but twice, something has caused this black hole to change its spin axis."

According to the scenario presented by Hodges-Kluck and his colleagues, the spin axis of the black hole ran along a diagonal line from top-right to bottom-left. After a collision with a smaller galaxy, a jet powered by the black hole ignited, blowing away gas to form cavities in the hot gas to the top-right and bottom-left. Since the gas falling onto the black hole was not aligned with the spin of the black hole, the spin axis of the black hole rapidly changed direction, and the jets then pointed in a roughly top-left to bottom- right direction, creating cavities in the hot gas and radio emission in this direction.

Then, either a merging of the two central black holes from the colliding galaxies, or more gas falling onto the black hole caused the spin axis to jerk around to its present direction in roughly a left to right direction. These types of changes in the angle of the spin of a supermassive black hole have previously been suggested to explain X- shaped radio galaxies, but no convincing case has been made in any individual case.

"If we're right, our work shows that jets and cavities are like cosmic fossils that help trace the merger history of an active supermassive black hole and the galaxy it lives in," said Hodges-Kluck. “If even a fraction of X-shaped radio galaxies are produced by such "spin-flips", then their frequency may be important for estimating the detection rates with gravitational radiation missions."

These results appeared in a recent issue of The Astrophysical Journal Letters. 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.

More information, including images and other multimedia, can be found at:

http://chandra.harvard.edu
NASASpaceflight ISS Editor

Offline Space Pete

Re: NASA - Chandra X-Ray - updates
« Reply #6 on: 09/14/2010 09:26 pm »
Chandra Finds Evidence for Stellar Cannibalism.

• BP Psc is a star like our Sun, but one that is more evolved, about
  1,000 light years away.

• New evidence from Chandra supports the case that BP Psc is not a
  very young star as previously thought.

• Rather, BP has spent its nuclear fuel and expanded into its "red giant"
  phase – likely consuming a star or planet in the process.

• Studying this type of stellar "cannibalism" may help astronomers better
  understand how stars and planets interact as they age.

The composite image on the left shows X-ray and optical data for BP Piscium (BP Psc), a more evolved version of our Sun about 1,000 light years from Earth. Chandra X-ray Observatory data are colored in purple, and optical data from the 3-meter Shane telescope at Lick Observatory are shown in orange, green and blue. BP Psc is surrounded by a dusty and gaseous disk and has a pair of jets several light years long blasting out of the system. A close-up view is shown by the artist's impression on the right. For clarity a narrow jet is shown, but the actual jet is probably much wider, extending across the inner regions of the disk. Because of the dusty disk, the star's surface is obscured in optical and near-infrared light. Therefore, the Chandra observation is the first detection of this star in any wavelength.

The disk and the jets, seen distinctly in the optical data, provide evidence for a recent and catastrophic interaction in which BP Psc consumed a nearby star or giant planet. This happened when BP Psc ran out of nuclear fuel and expanded into its "red giant" phase.

Jets and a disk are often characteristics of very young stars, so astronomers thought BP Psc might be one as well. However, the new Chandra results argue against this interpretation, because the X-ray source is fainter than expected for a young star. Another argument previously used against the possible youth of BP Psc was that it is not located near any star-forming cloud and there are no other known young stars in its immediate vicinity. The Chandra image supports this absence of a cluster of young stars, since multiwavelength studies show that most of the X-ray sources in the composite image are likely to be rapidly growing supermassive black holes in the centers of distant galaxies.

Source (with accompanying image).
NASASpaceflight ISS Editor

Offline Space Pete

Re: NASA - Chandra X-Ray - updates
« Reply #7 on: 09/15/2010 10:19 pm »
Enigmatic Star Devours Companion; Possibly Pregnant with Second-generation Planets.

An astronomer may have caught a cannibalistic star in the act of devouring a companion and making a second generation of exoplanets from the resulting orbiting disk.

Using data from NASA’s Chandra X-ray Observatory, Joel Kastner, professor at Rochester Institute of Technology, has found evidence that a variable star in the constellation of Pisces, BP Piscium, is not the young star it appears to be, but is more likely a one billion-year-old red giant that has gobbled up a star or planet in its vicinity.

The star’s extreme properties have puzzled astronomers since Kastner and Ben Zuckerman, professor at the University of California, Los Angeles, first looked at BP Psc 15 years ago. Conflicting characteristics have defied the star’s classification as either young or old.

Kastner attributes the star’s potentially deceptive youthful appearance to two things: an orbiting disk that resembles the sort that forms planets around young stars and prominent jets extending from the poles of the star that eject material at high velocity. A typical young star accretes material from its orbiting disk as debris from the disk falls onto the star. In turn, the star incorporates about 90 percent of the material and recycles the remainder through its jets.

Crucial details left Kastner and his colleagues doubtful about the youth of the star, however. For one thing, the star is isolated, whereas most young stars form in clusters.

“As hard as people have looked, they have not been able to find a young star near BP Psc,” says Kastner, a professor in RIT’s Chester F. Carlson Center for Imaging Science. “That was one of several things that made Ben [Zuckerman] and me suspect that it wasn’t actually young.”

Second, this enigmatic star in the Pisces constellation lacks the large abundance of lithium on its surface that is typical of young stars. Older stars lose their lithium in nuclear reactions when mixing and churning folds the gases into the center of the star. According to Kastner, other key spectral features involving the star’s radius and surface gravity also point to the star’s advanced age.

Kastner is ready to close the debate with data obtained from the Chandra X-ray Observatory.

“The last piece of evidence, which, to me, is the nail in the coffin that BP Psc is old rather than young, is that its rate of X-ray production is very similar to old, yet rapidly spinning, giant stars that have surface temperatures similar to BP Psc,” Kastner says.

If BP Psc were a young star, it would emit X-rays in the hundreds, even up to a few thousand, in a day’s observing time with Chandra, Kastner notes. Instead, it is a weak X-ray source.

“We stared at BP Psc for one day with Chandra and only detected about 18 X-rays,” Kastner says. “We could almost name them.”

The rate of X-rays coming from the star are in keeping with a class of rapidly rotating old stars having similar temperature to BP Psc, Kastner says. This class is thought to be the result of one star swallowing another close companion star. These giant stars’ rates of X-ray production and their rapid spinning suggest they have engaged in such stellar cannibalism.

“These giant stars’ companions have fallen inside and spun them up,” Kastner says. “But we’ve never actually caught one in the act. I think BP Psc is an example of such an interaction. Our working speculation is that we are observing the star right at the point at which it has swallowed its companion and hence formed a disk. Some of the material that used to be its companion has fallen onto the star and some has been shot out at high speeds, and that’s what we’re seeing.”

The enigmatic star is likely about a billion years old and just entering the red giant stage in its life cycle in which it swells to digest its star or planet companion.

“It could be a small star or a large planet,” Kastner says. “We don’t know which it could be, but we’re very interested in finding out.”

More work needs to be done on the variable star in Kastner’s study. Astronomers are presently deciphering infrared spectra to determine the specific kinds of dust orbiting the star and look for evidence of planets forming in the disk.

“In order to understand the extrasolar planets that are now being discovered by the dozen, we need to figure out how planets might be forming and therefore where we should go look for them,” Kastner says. “I think this object is especially interesting because it gives us a good shot at finding young planets around an old star.”

Kastner’s findings were published in a recent issue of the Astrophysical Journal (Letters), and include contributions by Rodolfo Montez, a doctoral candidate in the astrophysical sciences and technology program in RIT’s Center for Imaging Science. Other co-authors were Nicolas Grosso of the University of Strasbourg, Ben Zuckerman from University of California, Los Angeles, Marshall Perrin from the Space Telescope Science Institute, Thierry Forveille of the Grenoble Astrophysics Laboratory in France and James Graham from University of California, Berkeley.

About RIT: Rochester Institute of Technology is internationally recognized for academic leadership in computing, engineering, imaging technology, and fine and applied arts, in addition to unparalleled support services for students with hearing loss. Nearly 17,000 full- and part-time students are enrolled in more than 200 career-oriented and professional programs at RIT, and its cooperative education program is one of the oldest and largest in the nation.

For two decades, U.S. News & World Report has ranked RIT among the nation’s leading comprehensive universities. RIT is featured in The Princeton Review’s 2011 edition of The Best 373 Colleges and the 2011 edition of The Fiske Guide to College.

Source.
NASASpaceflight ISS Editor

Offline Space Pete

Re: NASA - Chandra X-Ray - updates
« Reply #8 on: 09/15/2010 10:56 pm »
Chandra Finds Evidence for Stellar Cannibalism.
 
Evidence that a star has recently engulfed a companion star or a giant planet has been found using NASA's Chandra X-ray Observatory. The likely existence of such a "cannibal" star provides new insight into how stars and the planets around them may interact as they age.

The star in question, known as BP Piscium (BP Psc), appears to be a more evolved version of our Sun, but with a dusty and gaseous disk surrounding it. A pair of jets several light years long blasting out of the system in opposite directions has also been seen in optical data. While the disk and jets are characteristics of a very young star, several clues -- including the new results from Chandra -- suggest that BP Psc is not what it originally appeared to be.

Instead, astronomers have suggested that BP Psc is an old star in its so-called red giant phase. And, rather than being hallmarks of its youth, the disk and jets are, in fact, remnants of a recent and catastrophic interaction whereby a nearby star or giant planet was consumed by BP Psc.

When stars like the Sun begin to run of nuclear fuel, they expand and shed their outer layers. Our Sun, for example, is expected to swell so that it nearly reaches or possibly engulfs Earth, as it becomes a red giant star.

"It appears that BP Psc represents a star-eat-star Universe, or maybe a star-eat-planet one," said Joel Kastner of the Rochester Institute of Technology, who led the Chandra study. "Either way, it just shows it's not always friendly out there."

Several pieces of information have led astronomers to rethink how old BP Psc might be. First, BP Psc is not located near any star-forming cloud, and there are no other known young stars in its immediate vicinity. Secondly, in common with most elderly stars, its atmosphere contains only a small amount of lithium. Thirdly, its surface gravity appears to be too weak for a young star and instead matches up with one of an old red giant.

Chandra adds to this story. Young, low-mass stars are brighter than most other stars in X-rays, and so X-ray observations can be used as a sign of how old a star may be. Chandra does detect X-rays from BP Psc, but at a rate that is too low to be from a young star. Instead, the X-ray emission rate measured for BP Psc is consistent with that of rapidly rotating giant stars.

The spectrum of the X-ray emission -- that is how the amount of X-rays changes with wavelength -- is consistent with flares occurring on the surface of the star, or with interactions between the star and the disk surrounding it. The magnetic activity of the star itself might be generated by a dynamo caused by its rapid rotation. This rapid rotation can be caused by the engulfment process.

"It seems that BP Psc has been energized by its meal," said co-author Rodolfo (Rudy) Montez Jr., also from the Rochester Institute of Technology.

The star's surface is obscured throughout the visible and near-infrared bands, so the Chandra observation represents the first detection at any wavelength of BP Psc itself.

"BP Psc shows us that stars like our Sun may live quietly for billions of years," said co-author David Rodriguez from UCLA, "but when they go, they just might take a star or planet or two with them."

Although any close-in planets were presumably devastated when BP Psc turned into a giant star, a second round of planet formation might be occurring in the surrounding disk, hundreds of millions of years after the first round. A new paper using observations with the Spitzer Space Telescope has reported possible evidence for a giant planet in the disk surrounding BP Psc. This might be a newly formed planet or one that was part of the original planetary system.

"Exactly how stars might engulf other stars or planets is a hot topic in astrophysics today," said Kastner. "We have many important details that we still need to work out, so objects like BP Psc are really exciting to find."

These results appeared in The Astrophysical Journal Letters. Other co-authors on the study were Nicolas Grosso of the University of Strasbourg, Ben Zuckerman from UCLA, Marshall Perrin from the Space Telescope Science Institute, Thierry Forveille of the Grenoble Astrophysics Laboratory in France and James Graham from University of California, Berkeley.

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.

More information, including images and other multimedia, can be found at: http://chandra.harvard.edu.

Source (with accompanying image).
« Last Edit: 09/15/2010 10:58 pm by Space Pete »
NASASpaceflight ISS Editor

Offline Space Pete

Re: NASA - Chandra X-Ray - updates
« Reply #9 on: 10/05/2010 07:47 pm »
G327.1-1.1: Pushing the Envelope.

• G327 is the aftermath of a star that exploded as a supernova.

• In the composite, X-rays are blue, radio data are red and yellow, and
  infrared data show the stars in the field.

• A rapidly spinning neutron star left behind is producing the wind of
  relativistic particles seen in X-rays.

G327.1-1.1 is the aftermath of a massive star that exploded as a supernova in the Milky Way galaxy. A highly magnetic, rapidly spinning neutron star called a pulsar  was left behind after the explosion and is producing a wind of relativistic particles, seen in X-rays by Chandra and XMM-Newton (blue) as well as in the radio data (red and yellow). This structure is called a pulsar wind nebula. The likely location of the spinning neutron star is shown in the labeled version. The large red circle shows radio emission from the blast wave, and the composite image also contains infrared data from the 2MASS survey (red, green, and blue) that show the stars in the field.

No clear explanation is yet known for the unusual nature of G327.1-1.1, including the off-center position of the pulsar wind nebula seen in the radio data and the comet-like shape of the X-ray emission. One possibility is that we are seeing the effects of a shock wave bouncing backwards off of the shell of material swept up by the blast wave produced by the explosion, the so-called "reverse shock" from the blast wave. The pulsar is moving upwards, away from the center of the explosion, but the pulsar wind nebula is being swept towards the bottom-left of the image by the reverse shock wave that is also traveling towards the bottom-left. The direction of the pulsar's motion and of the reverse shock are shown in the labeled version.

The X-ray observations allow scientists to estimate the energy released during the supernova explosion and the age of the remnant, as well as the amount of material being swept up as the blast wave from the explosion expands. The faint bubble that the pulsar appears to be creating may also be revealing the fresh pulsar wind being blown into the region cleared out by the reverse shock.

A paper describing these results appeared in The Astrophysical Journal in February 2009 with Tea Temim of the Harvard-Smithsonian Center for Astrophysics (CfA), Patrick Slane (CfA), Bryan Gaensler (University of Sydney), Jack Hughes (Rutgers) and Eric Van Der Swaluw (Royal Netherlands Meterological Institute) as authors.


http://chandra.harvard.edu/photo/2010/g327
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Offline Space Pete

Re: NASA - Chandra X-Ray - updates
« Reply #10 on: 10/16/2010 12:45 am »
What Lies Beneath? Magnetar Enigma Deepens.

• A slowly rotating neutron star with a weak surface magnetic field is
  giving off bursts of X-rays and gamma-rays.

• This discovery may have implications for how some of the most
  powerful magnets in the cosmos evolve.

• Several NASA telescopes including Chandra, Swift, RXTE, XMM-Newton
  and Fermi contributed to these results.

Observations with NASA's Chandra, Swift, and Rossi X-ray observatories, Fermi Gamma-ray Space Telescope, and ESA's XMM-Newton have revealed that a slowly rotating neutron star with an ordinary surface magnetic field is giving off bursts of X-rays and gamma rays. This discovery may indicate the presence of an internal magnetic field much more intense than the surface magnetic field, with implications for how the most powerful magnets in the cosmos evolve.

The neutron star, SGR 0418+5729, was discovered on June 5, 2009 when the Fermi Gamma-ray Space Telescope detected bursts of gamma-rays from this object. Follow-up observations four days later with the Rossi X-Ray Timing Explorer (RXTE) showed that, in addition to sporadic X-ray bursts, the neutron star exhibits persistent X-ray emission with regular pulsations that indicate that the star has a rotational period of 9.1 seconds. RXTE was able to monitor this activity for about 100 days. This behavior is similar to a class of neutron stars called magnetars, which have strong to extreme magnetic fields 20 to 1000 times above the average of the galactic radio pulsars.

As neutron stars rotate, the radiation of low frequency electromagnetic waves or winds of high-energy particles carry energy away from the star, causing the rotation rate of the star to gradually decrease. Careful monitoring of SGR 0418 was possible because Chandra and XMM-Newton were able to measure its pulsation period even though it faded by a factor of 10 after the initial detection. What sets SGR 0418 apart from other magnetars is that careful monitoring over a span of 490 days has revealed no detectable decrease in its rotation rate.

The lack of rotational slowing implies that the radiation of low frequency waves must be weak, and hence the surface magnetic field must be much weaker than normal. But this raises another question: where does the energy come from to power bursts and the persistent X-ray emission from the source?

The generally accepted answer for magnetars is that the energy to power the X- and gamma-ray emission comes from an internal magnetic field that has been twisted and amplified in the turbulent interior of the neutron star, as depicted in the illustration above. Theoretical studies indicate that if the internal field becomes about ten or more times stronger than the surface field, the decay or untwisting of the field can lead to the production of steady and bursting X-ray emission through the heating of the neutron star crust or the acceleration of particles.

A crucial question is how large an imbalance can be maintained between the surface and interior fields. SGR 0418 represents an important test case. The observations already imply an imbalance of between 50 and 100. If further observations by Chandra push the surface magnetic field limit lower, then theorists may have to dig deeper for an explanation of this enigmatic object.

This discovery is the result of an international teamwork from CSIC-IEEC, INAF, University of Padua, MSSL-UCL, CEA-Saclay, Sabanci University and NASA's Marshall Space Flight Center (MSFC). These results appear in the October 14th issue of Science Express, which provides electronic publication of selected Science papers in advance of print. NASA's MSFC 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.

Fast Facts for SGR 0418+5729:

Credit                       Illustration: NASA/CXC/M.Weiss
Category                  Neutron Stars/X-ray Binaries
Coordinates (J2000)  RA 04h 18m 33.90s | Dec +57° 32' 22.90''
Constellation            Camelopardalis
Observation Dates    Jul 23, 2010
Observation Time      6 hours 56 min
Obs. IDs                  12312
Instrument                ACIS
References               Rea, N, et al, 2010, in press
Distance Estimate     6500 light years
Release Date            October 14, 2010


http://chandra.harvard.edu/photo/2010/sgr0418
« Last Edit: 10/16/2010 12:46 am by Space Pete »
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Online jacqmans

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Re: NASA - Chandra X-Ray - updates
« Reply #11 on: 11/10/2010 04:33 pm »
MEDIA ADVISORY: M10-157

NASA ANNOUNCES TELEVISED CHANDRA NEWS CONFERENCE

WASHINGTON -- NASA will hold a news conference at 12:30 p.m. EST on
Monday, Nov. 15, to discuss the Chandra X-ray Observatory's discovery
of an exceptional object in our cosmic neighborhood.

The news conference will originate from NASA Headquarters' television
studio, 300 E St. SW in Washington and carried live on NASA TV.

Media representatives may attend the conference, join by phone or ask
questions from participating NASA locations. To RSVP or obtain
dial-in information, journalists must send their name, affiliation
and telephone number to Trent Perrotto at: [email protected]
by 10 a.m. EST on Nov. 15. Reporters wishing to attend the conference
in-person must have a valid press credential for access. Non-U.S.
media also must bring passports.

Scientists involved in the research will be available to answer
questions. Panelists providing analysis of the research include:
- Jon Morse, director, Astrophysics Division, NASA Headquarters in
Washington
- Kimberly Weaver, astrophysicist, NASA's Goddard Space Flight Center,
Greenbelt, Md.
- Alex Filippenko, astrophysicist, University of California, Berkeley

For NASA TV streaming video, downlink and further information, visit:


http://www.nasa.gov/ntv


For more information about NASA's Chandra X-ray Observatory, visit:


http://www.nasa.gov/chandra




http://chandra.harvard.edu   


-end-

Jacques :-)

Offline Bubbinski

Re: NASA - Chandra X-Ray - updates
« Reply #12 on: 11/14/2010 06:13 am »
I will be watching this space on Monday.  I wish I could be watching NASA TV but I won't be able to access it on my work floor.

If it's a televised news conference I imagine it would be a pretty important find, maybe even something that might be important for us on earth?  Or at least something that will rewrite all the textbooks?  We'll see.
I'll even excitedly look forward to "flags and footprints" and suborbital missions. Just fly...somewhere.

Offline D.A.

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Re: NASA - Chandra X-Ray - updates
« Reply #13 on: 11/15/2010 04:35 pm »
They've discovered the youngest nearby (52.5 Mlys) black hole yet, formed by supernova 1979C.
« Last Edit: 11/15/2010 04:37 pm by D.A. »

Offline cgrunska

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Re: NASA - Chandra X-Ray - updates
« Reply #14 on: 11/15/2010 04:44 pm »
what's that mean for laymen?

Offline D.A.

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Re: NASA - Chandra X-Ray - updates
« Reply #15 on: 11/15/2010 05:14 pm »
They also discussed the possibility of it being a pulsar wind nebula but at this time they cannot tell which of the two it is yet. Kimberly Weaver was leaning towards a black hole though. The SN 1979C is unlike any other SNR they've seen so that one was one of the reasons Kimberly was leaning towards a black hole.


Here's an NASA article on it:

http://www.nasa.gov/mission_pages/chandra/news/H-10-299.html

« Last Edit: 11/15/2010 05:18 pm by D.A. »

Online jacqmans

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Re: NASA - Chandra X-Ray - updates
« Reply #16 on: 11/15/2010 08:47 pm »
RELEASE: 10-299

NASA'S CHANDRA FINDS YOUNGEST NEARBY BLACK HOLE

WASHINGTON -- Astronomers using NASA's Chandra X-ray Observatory have
found evidence of the youngest black hole known to exist in our
cosmic neighborhood. The 30-year-old black hole provides a unique
opportunity to watch this type of object develop from infancy.

The black hole could help scientists better understand how massive
stars explode, which ones leave behind black holes or neutron stars,
and the number of black holes in our galaxy and others.

The 30-year-old object is a remnant of SN 1979C, a supernova in the
galaxy M100 approximately 50 million light years from Earth. Data
from Chandra, NASA's Swift satellite, the European Space Agency's
XMM-Newton and the German ROSAT observatory revealed a bright source
of X-rays that has remained steady during observation from 1995 to
2007. This suggests the object is a black hole being fed either by
material falling into it from the supernova or a binary companion.

"If our interpretation is correct, this is the nearest example where
the birth of a black hole has been observed," said Daniel Patnaude of
the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass.
who led the study.

The scientists think SN 1979C, first discovered by an amateur
astronomer in 1979, formed when a star about 20 times more massive
than the sun collapsed. Many new black holes in the distant universe
previously have been detected in the form of gamma-ray bursts (GRBs).


However, SN 1979C is different because it is much closer and belongs
to a class of supernovas unlikely to be associated with a GRB. Theory
predicts most black holes in the universe should form when the core
of a star collapses and a GRB is not produced.

"This may be the first time the common way of making a black hole has
been observed," said co-author Abraham Loeb, also of the
Harvard-Smithsonian Center for Astrophysics. "However, it is very
difficult to detect this type of black hole birth because decades of
X-ray observations are needed to make the case."

The idea of a black hole with an observed age of only about 30 years
is consistent with recent theoretical work. In 2005, a theory was
presented that the bright optical light of this supernova was powered
by a jet from a black hole that was unable to penetrate the hydrogen
envelope of the star to form a GRB. The results seen in the
observations of SN 1979C fit this theory very well.

Although the evidence points to a newly formed black hole in SN 1979C,
another intriguing possibility is that a young, rapidly spinning
neutron star with a powerful wind of high energy particles could be
responsible for the X-ray emission. This would make the object in SN
1979C the youngest and brightest example of such a "pulsar wind
nebula" and the youngest known neutron star. The Crab pulsar, the
best-known example of a bright pulsar wind nebula, is about 950 years
old.

"It's very rewarding to see how the commitment of some of the most
advanced telescopes in space, like Chandra, can help complete the
story," said Jon Morse, head of the Astrophysics Division at NASA's
Science Mission Directorate.

The results will appear in the New Astronomy journal in a paper by
Patnaude, Loeb, and Christine Jones of the Harvard-Smithsonian Center
for Astrophysics. NASA's Marshall Space Flight Center in Huntsville,
Ala., manages the Chandra program for the agency's Science Mission
Directorate in Washington. The Smithsonian Astrophysical Observatory
controls Chandra's science and flight operations from Cambridge.

For more information about Chandra, including images and other
multimedia, visit:



http://chandra.nasa.gov

Jacques :-)

Online jacqmans

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Re: NASA - Chandra X-Ray - updates
« Reply #17 on: 06/15/2011 05:30 pm »
RELEASE: 11-183

NASA'S CHANDRA FINDS MASSIVE BLACK HOLES COMMON IN EARLY UNIVERSE

WASHINGTON -- Using the deepest X-ray image ever taken, astronomers
found the first direct evidence that massive black holes were common
in the early universe. This discovery from NASA's Chandra X-ray
Observatory shows that very young black holes grew more aggressively
than previously thought, in tandem with the growth of their host
galaxies.

By pointing Chandra at a patch of sky for more than six weeks,
astronomers obtained what is known as the Chandra Deep Field South
(CDFS). When combined with very deep optical and infrared images from
NASA's Hubble Space Telescope, the new Chandra data allowed
astronomers to search for black holes in 200 distant galaxies, from
when the universe was between about 800 million to 950 million years
old.

"Until now, we had no idea what the black holes in these early
galaxies were doing, or if they even existed," said Ezequiel Treister
of the University of Hawaii, lead author of the study appearing in
the June 16 issue of the journal Nature. "Now we know they are there,
and they are growing like gangbusters."

The super-sized growth means that the black holes in the CDFS are less
extreme versions of quasars -- very luminous, rare objects powered by
material falling onto supermassive black holes. However, the sources
in the CDFS are about a hundred times fainter and the black holes are
about a thousand times less massive than the ones in quasars.

The observations found that between 30 and 100 percent of the distant
galaxies contain growing supermassive black holes. Extrapolating
these results from the small observed field to the full sky, there
are at least 30 million supermassive black holes in the early
universe. This is a factor of 10,000 larger than the estimated number
of quasars in the early universe.

"It appears we've found a whole new population of baby black holes,"
said co-author Kevin Schawinski of Yale University. "We think these
babies will grow by a factor of about a hundred or a thousand,
eventually becoming like the giant black holes we see today almost 13
billion years later."

A population of young black holes in the early universe had been
predicted, but not yet observed. Detailed calculations show that the
total amount of black hole growth observed by this team is about a
hundred times higher than recent estimates.

Because these black holes are nearly all enshrouded in thick clouds of
gas and dust, optical telescopes frequently cannot detect them.
However, the high energies of X-ray light can penetrate these veils,
allowing the black holes inside to be studied.

Physicists studying black holes want to know more how the first
supermassive black holes were formed and how they grow. Although
evidence for parallel growth of black holes and galaxies has been
established at closer distances, the new Chandra results show that
this connection starts earlier than previously thought, perhaps right
from the origin of both.

"Most astronomers think in the present-day universe, black holes and
galaxies are somehow symbiotic in how they grow," said Priya
Natarajan, a co-author from Yale University. "We have shown that this
codependent relationship has existed from very early times."

It has been suggested that early black holes would play an important
role in clearing away the cosmic "fog" of neutral, or uncharged,
hydrogen that pervaded the early universe when temperatures cooled
down after the Big Bang. However, the Chandra study shows that
blankets of dust and gas stop ultraviolet radiation generated by the
black holes from traveling outwards to perform this "reionization."
Therefore, stars and not growing black holes are likely to have
cleared this fog at cosmic dawn.

Chandra is capable of detecting extremely faint objects at vast
distances, but these black holes are so obscured that relatively few
photons can escape and hence they could not be individually detected.
Instead, the team used a technique that relied on Chandra's ability
to accurately determine the direction from which the X-rays came to
add up all the X-ray counts near the positions of distant galaxies
and find a statistically significant signal.

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

More information, including images and other multimedia, can be found
at:



http://www.nasa.gov/chandra

Jacques :-)

Online jacqmans

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Re: NASA - Chandra X-Ray - updates
« Reply #18 on: 07/27/2011 06:05 pm »
RELEASE: 11-247

NASA'S CHANDRA OBSERVATORY IMAGES GAS FLOWING TOWARD BLACK HOLE

WASHINGTON -- The flow of hot gas toward a black hole has been clearly
imaged for the first time in X-rays. The observations from NASA's
Chandra X-ray Observatory will help tackle two of the most
fundamental problems in modern astrophysics: understanding how black
holes grow and how matter behaves in their intense gravity.

The black hole is at the center of a large galaxy known as NGC 3115,
which is located about 32 million light years from Earth. A large
amount of previous data has shown material falling toward and onto
black holes, but none with this clear a signature of hot gas.

By imaging the hot gas at different distances from this supermassive
black hole, astronomers have observed a critical threshold where the
motion of gas first becomes dominated by the black hole's gravity and
falls inward. This distance from the black hole is known as the
"Bondi radius."

"It's exciting to find such clear evidence for gas in the grip of a
massive black hole," said Ka-Wah Wong of the University of Alabama,
who led the study that appears in the July 20th issue of The
Astrophysical Journal Letters. "Chandra's resolving power provides a
unique opportunity to understand more about how black holes capture
material by studying this nearby object."

As gas flows toward a black hole, it becomes squeezed, making it
hotter and brighter, a signature now confirmed by the X-ray
observations. The researchers found the rise in gas temperature
begins about 700 light years from the black hole, giving the location
of the Bondi radius. This suggests the black hole in the center of
NGC 3115 has a mass about two billion times that of the sun, making
it the closest black hole of that size to Earth.

The Chandra data also show the gas close to the black hole in the
center of the galaxy is denser than gas further out, as predicted.
Using the observed properties of the gas and theoretical assumptions,
the team then estimated that each year gas weighing about 2 percent
the mass of the sun is being pulled across the Bondi radius toward
the black hole.

Making certain assumptions about how much of the gas's energy changes
into radiation, astronomers would expect to find a source that is
more than a million times brighter in X-rays than what is seen in NGC
3115.

"A leading mystery in astrophysics is how the area around massive
black holes can stay so dim, when there's so much fuel available to
light up," said co-author Jimmy Irwin, also of the UA in Tuscaloosa.
"This black hole is a poster child for this problem."

There are at least two possible explanations for this discrepancy. The
first is that much less material actually falls onto the black hole
than flows inside the Bondi radius. Another possibility is that the
conversion of energy into radiation is much less efficient than is
assumed.

Different models describing the flow of material onto the black hole
make different predictions for how quickly the density of the gas is
seen to rise as it approaches the black hole. A more precise
determination of the rise in density from future observations should
help astronomers rule out some of these models.

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

More information, including images and other multimedia, can be found
at:


http://chandra.nasa.gov

and

http://chandra.si.edu

Jacques :-)

Offline wjbarnett

Re: NASA - Chandra X-Ray - updates
« Reply #19 on: 08/26/2011 12:54 am »
Very interesting discussion of the "safe mode" issue back in July:
http://spectrum.ieee.org/aerospace/astrophysics/the-rescue-of-the-chandra-xray-observatory
Jack

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