More Images of Chandra Deep Field South
Correction: After this paper (Treister et al. 2011) was published and publicized a problem was discovered with the background subtraction used. Analysis by several groups, including the Treister et al. team, plus Willott (2011) and Cowie et al. (2012), shows that a significant detection of AGN (growing black holes) in the early universe can no longer be claimed.
Editor's Note: Honest errors such as this are part of the scientific process, especially on the frontiers of discovery. To quote Nobel laureate Frank Wilczek, "If you don't make mistakes, you're not working on hard enough problems. And that's a big mistake."
Cowie, L. et al. 2012, ApJ, in press
Treister, E. et al. 2011, Nature, 474, 356
Willott, C. 2011, ApJ, 742, L8
Chandra X-ray Full-field Image of CDFS
This image is what is known as the Chandra Deep Field South, a 4-million-second exposure made by NASA's Chandra X-ray Observatory. Located in the constellation of Fornax, this is the deepest X-ray image ever obtained of the sky. Most of the sources in this image contain rapidly growing supermassive black holes. Some of these black holes are seen to exist when the Universe is less than about 950 million years old.
(Credit: X-ray: NASA/CXC/U.Hawaii/E.Treister et al; Optical: NASA/STScI/S.Beckwith et)
X-ray & Optical Images of CDFS
This image shows a close-up of the 4 million second X-ray exposure of the
Chandra Deep Field South, as well an optical and infrared
image from the Hubble Space Telescope of the same field. The two small Chandra sources shown separately at right, show all of the
low and high energy X-rays that have been added up at the positions of
these galaxies. This shows that growing black holes have been detected in
30% to 100% of the distant galaxies, and that the black holes are heavily
obscured by dust and gas.
(Credit: X-ray: NASA/CXC/U.Hawaii/E.Treister et al; Optical: NASA/STScI/S.Beckwith et al)
Illustration of Baby Galaxy and Galaxy Core
This artist's impression shows a very young galaxy located in the early
Universe less than one billion years after the Big Bang. The distorted
appearance of the galaxy is caused by the large number of mergers occurring
at this early epoch, and the blue regions mark where star formation is
occurring at a high rate. The core of the galaxy is embedded within heavy
veils of dust and gas. A cut-out from the core shows that this dust and gas
is hiding very bright radiation from the very center of the galaxy,
produced by a rapidly growing supermassive black hole.
Illustration of Core of Galaxy and Its Supermassive Black Hole
This artist's impression shows a growing supermassive black hole located at
the center of a galaxy's core. The black hole and the copious amounts of
optical and ultraviolet radiation produced by gas falling onto it - as
shown by the cut-out - are hidden by a heavy veil of dust and gas. However,
extremely energetic X-rays can penetrate this dust and gas.
Illustration of Baby Black Hole
This is an artist's impression of a growing supermassive black hole located
in the early Universe, showing a disk of gas rotating around the
central object that generates copious amounts of radiation. This gas
is destined to be consumed by the black hole. The black hole's mass is less
than one hundredth of the mass it will have when the Universe reaches
its present day age of about 13.7 billion years.
Return to Chandra Deep Field South (June 15, 2011)
Illustration of Reionization
This artist's impression shows a timeline summarising the evolution of the
Universe running from left to right, where the Big Bang is on the left and
the age of the Universe is about two billion years on the right. This shows
how the cosmic "fog" of neutral (uncharged) hydrogen pervading the early
Universe is cleared by the first objects to emit radiation. It has been
suggested that early black holes would play an important role in ionizing
the hydrogen, a process called "reionization". However, the new Chandra
study shows that blankets of dust and gas stop ultraviolet radiation
generated by the black holes from traveling outwards to take part in
reionization. Therefore, stars and not growing black holes are likely to
have cleared this cosmic fog.