This composite
image shows the most distant X-ray jet ever observed. X-ray data from
NASA's Chandra X-ray Observatory are shown in blue, radio data from the
NSF's Very Large Array are shown in purple and optical data from NASA's
Hubble Space Telescope are shown in yellow. The jet was produced by a
quasar named GB 1428+4217, or GB 1428 for short, and is located 12.4
billion light years from Earth. Labels for the quasar and jet can be
seen by mousing over the image. The shape of the jet is very similar in
the X-ray and radio data.
Giant black holes at the centers of galaxies can pull in matter at a rapid rate producing the quasar phenomenon. The energy released as particles fall toward the black hole generates intense radiation and powerful beams of high-energy particles that blast away from the black hole at nearly the speed of light. These particle beams can interact with magnetic fields or ambient photons to produce jets of radiation.
As the electrons in the jet fly away from the quasar, they move through a sea of background photons left behind after the Big Bang. When a fast-moving electron collides with one of these so-called cosmic microwave background photons, it can boost the photon’s energy into the X-ray band. Because the quasar is seen when the universe is at an age of about 1.3 billion years, less than 10% of its current value, the cosmic background radiation is a thousand times more intense than it is now. This makes the jet much brighter, and compensates in part for the dimming due to distance.
While there is another possible source of X-rays for the jet - radiation from electrons spiraling around magnetic field lines in the jet - the authors favor the idea that the cosmic background radiation is being boosted because the jet is so bright.
The researchers think the length of the jet in GB 1428 is at least 230,000 light years, or about twice the diameter of the entire Milky Way galaxy. This jet is only seen on one side of the quasar in the Chandra and VLA data. When combined with previously obtained evidence, this suggests the jet is pointed almost directly toward us. This configuration would boost the X-ray and radio signals for the observed jet and diminish those for a jet presumably pointed in the opposite direction.
This result appeared in the Sept. 1, 2012 issue of The Astrophysical Journal Letters.
Credits: X-ray: NASA/CXC/NRC/C.Cheung et al; Optical: NASA/STScI; Radio: NSF/NRAO/VLA
› Read more/access all images
› Chandra's Flickr photoset
Giant black holes at the centers of galaxies can pull in matter at a rapid rate producing the quasar phenomenon. The energy released as particles fall toward the black hole generates intense radiation and powerful beams of high-energy particles that blast away from the black hole at nearly the speed of light. These particle beams can interact with magnetic fields or ambient photons to produce jets of radiation.
As the electrons in the jet fly away from the quasar, they move through a sea of background photons left behind after the Big Bang. When a fast-moving electron collides with one of these so-called cosmic microwave background photons, it can boost the photon’s energy into the X-ray band. Because the quasar is seen when the universe is at an age of about 1.3 billion years, less than 10% of its current value, the cosmic background radiation is a thousand times more intense than it is now. This makes the jet much brighter, and compensates in part for the dimming due to distance.
While there is another possible source of X-rays for the jet - radiation from electrons spiraling around magnetic field lines in the jet - the authors favor the idea that the cosmic background radiation is being boosted because the jet is so bright.
The researchers think the length of the jet in GB 1428 is at least 230,000 light years, or about twice the diameter of the entire Milky Way galaxy. This jet is only seen on one side of the quasar in the Chandra and VLA data. When combined with previously obtained evidence, this suggests the jet is pointed almost directly toward us. This configuration would boost the X-ray and radio signals for the observed jet and diminish those for a jet presumably pointed in the opposite direction.
This result appeared in the Sept. 1, 2012 issue of The Astrophysical Journal Letters.
Credits: X-ray: NASA/CXC/NRC/C.Cheung et al; Optical: NASA/STScI; Radio: NSF/NRAO/VLA
› Read more/access all images
› Chandra's Flickr photoset
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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1 comentario:
¿Podría un agujero negro devorar una galaxia completa?
Esto es escasamente probable, aunque los astrónomos tienen la certeza de que los agujeros negros existen en los corazones de casi todas las galaxias. En todo caso el tamaño de los mismos es notablemente inferior a las galaxias que los hospedan.
Esto significa que, mientras la gravedad es muy fuerte cerca de un agujero negro, la misma fuerza es bastante débil en las fronteras de aquella misma galaxia donde reside la súper masa negra.
Por consecuencia, aunque los agujeros negros dominan las regiones centrales de una galaxia, y muchas veces producen una cantidad de energía descomunal, no tienen la fuerza suficiente para devorar una galaxia completa.
Creo que no:
Los agujeros negros no tienen el tamaño ni la fuerza de gravedad suficiente para "tragar" la galaxia que los alberga.
BBC Mundo Noticias
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