Hola amigos: A VUELO DE UN QUINDE EL BLOG., la Agencia Espacial NASA, nos informa que su Telescopio Espacial CHANDRA, ha detectado un supermasivo agujero negro en el centro de la Vía Láctea; NASA nos dice : "Los astrónomos han detectado la mayor llamarada de rayos X nunca del agujero negro supermasivo en el centro de la Vía Láctea utilizando el Observatorio de Rayos X Chandra de la NASA. Este evento fue 400 veces más brillante que la emisión de rayos X que de costumbre desde el agujero negro.............."
Astronomers have detected the largest X-ray flare
ever from the supermassive black hole at the center of the Milky Way using
NASA’s Chandra X-ray Observatory. This event was 400 times brighter than the
usual X-ray output from the black hole. Credit: NASA/CXC/Northwestern
Univ/D.Haggard et al.
Image Credit:
NASA/CXC/Stanford/I. Zhuravleva et
al.
Astronomers have observed the largest X-ray flare ever detected from the
supermassive black hole at the center of the Milky Way galaxy. This event,
detected by NASA’s Chandra X-ray Observatory, raises questions about the
behavior of this giant black hole and its surrounding environment.
The supermassive black hole at the center of our galaxy, called Sagittarius
A*, or Sgr A*, is estimated to contain about 4.5 million times the mass of our
sun.
Astronomers made the unexpected discovery while using Chandra to observe how
Sgr A* would react to a nearby cloud of gas known as G2.
“Unfortunately, the G2 gas cloud didn’t produce the fireworks we were hoping
for when it got close to Sgr A*,” said lead researcher Daryl Haggard of Amherst
College in Massachusetts. “However, nature often surprises us and we saw
something else that was really exciting.”
On Sept. 14, 2013, Haggard and her team detected an X-ray flare from Sgr A*
400 times brighter than its usual, quiet state. This “megaflare” was nearly
three times brighter than the previous brightest X-ray flare from Sgr A* in
early 2012. After Sgr A* settled down, Chandra observed another enormous X-ray
flare 200 times brighter than usual on Oct. 20, 2014.
Astronomers estimate that G2 was closest to the black hole in the spring of
2014, 15 billion miles away. The Chandra flare observed in September 2013 was
about a hundred times closer to the black hole, making the event unlikely
related to G2.
The researchers have two main theories about what caused Sgr A* to erupt in
this extreme way. The first is that an asteroid came too close to the
supermassive black hole and was torn apart by gravity. The debris from such a
tidal disruption became very hot and produced X-rays before disappearing forever
across the black hole's point of no return, or event horizon.
“If an asteroid was torn apart, it would go around the black hole for a
couple of hours – like water circling an open drain – before falling in,” said
co-author Fred Baganoff of the Massachusetts Institute of Technology in
Cambridge, Massachusetts. “That’s just how long we saw the brightest X-ray flare
last, so that is an intriguing clue for us to consider.”
If this theory holds up, it means astronomers may have found evidence for the
largest asteroid to produce an observed X-ray flare after being torn apart by
Sgr A*.
A second theory is that the magnetic field lines within the gas flowing
towards Sgr A* could be tightly packed and become tangled. These field lines may
occasionally reconfigure themselves and produce a bright outburst of X-rays.
These types of magnetic flares are seen on the sun, and the Sgr A* flares have
similar patterns of intensity.
“The bottom line is the jury is still out on what’s causing these giant
flares from Sgr A*,” said co-author Gabriele Ponti of the Max Planck Institute
for Astrophysics in Garching, Germany. “Such rare and extreme events give us a
unique chance to use a mere trickle of infalling matter to understand the
physics of one of the most bizarre objects in our galaxy.”
In addition to the giant flares, the G2 observing campaign with Chandra also
collected more data on a magnetar: a neutron star with a strong magnetic field,
located close to Sgr A*. This magnetar is undergoing a long X-ray outburst, and
the Chandra data are allowing astronomers to better understand this unusual
object.
These results were presented at the 225th meeting of the American
Astronomical Society being held in Seattle. NASA's Marshall Space Flight Center
in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission
Directorate in Washington. The Smithsonian Astrophysical Observatory in
Cambridge, Massachusetts, controls Chandra's science and flight operations.
NASA is exploring our solar system and beyond to understand the universe and
our place in it. The agency seeks to unravel the secrets of our universe, its
origins and evolution, and search for life among the stars.
An interactive image, a podcast, and a video about the findings are available
at:
For more Chandra images, multimedia and related materials, visit:
NASA
Guillermo Gonzalo Sánchez Achutegui
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