Post by Andrei Tchentchik on Jun 26, 2019 18:38:29 GMT 2
(.#228).- Discovery of the oldest black hole in the universe, formidable colossus.iscovery of the oldest black hole in the universe, formidable colossus.
By Tristan Vey & Cyrille Vanlerberghe - Updated on 08/12/2017 at 13:53
Artist's impression of a hypermassive black hole growing from the material. Robin Dienel / Carnegie Institution for Science.
The very existence of this mastodon, 800 million times the mass of our Sun, as early in the history of the universe, is an enigma for astronomers.
He is as big as he is distant, and it is a real surprise. A hypermassive black hole, 800 million times the mass of our Sun, whose light took 13 billion years to reach us, by an international team of researchers (work published in Nature and The Astrophyscial Journal Letters) . It is an absolute distance record for an object of this type (the previous record dates from 2011), but also a weight record for a star as far away. "It is at least ten times larger than the previous supermassive black hole detected at this type of distance," says Bram Venemans, astronomer of the Max Planck Institute for Astronomy in Heidelberg, Germany, who coordinates with his colleague Fabian Walter looking for this type of objects in the confines of the visible universe for several years.
The discovery itself is credited to Magellan telescopes at the Las Campanas observatory in Chile, after a systematic search on a very large number of stars with NASA's WISE space telescope. The black hole was then the subject of intensive observation campaigns with the VLA (New Mexico) and NOEMA radio telescope networks of Iram, located in the French Alps. The latter succeeded in detecting the galaxy in which the mastodon was hiding .
The latter was betrayed by the gargantuan meal he is eating. A disc of matter collapses in fact spiral in the mouth of the cosmic ogre. When falling, this matter heats up and emits a very intense radiation, 40 trillion times brighter than our Sun. This type of black hole surprised in full feast has a name: this is called a quasar. These are among the brightest objects in the universe. There are several tens to discover at such distances, according to some estimates. European space satellites Euclid and American WFIRST will make their daily bread. The future successor of Hubble, the James Webb Space Telescope (JWST), too.
The light emitted by this hypermassive black hole took so long to reach us (more than 13 billion years) that we observe it as it was at a very remote time. In this case, 690 million years only after the Big Bang, less than 5% of the age of the universe. His early childhood in a way. "We were surprised to see that the black hole was so heavy," admits Bram Venemans. "It was really unexpected and it will give us constraints on the evolution of this type of objects in such a young universe."
A voracious embryo of a thousand solar masses?
Patrick Petitjean, astronomer at the Institute of Astrophysics of Paris and quasar specialist, explains that it would take a primordial black hole of a thousand solar masses to form such a mastodon within the time allowed by his young age. But we do not really know how such objects could be formed in the present universe. Stellar black holes, which are formed by the collapse of massive stars at the end of life, weigh at most only a few tens of solar masses. "In these very old times, the universe was denser," says the researcher. "Huge clouds of gas may have collapsed at once to directly form those big black holes of a few thousand solar masses."
These voracious "big embryos" would then have snatched large amounts of surrounding matter in a relatively short time on the astronomical scales to become such obese as greedy. But this scenario, as plausible as it is, is still far from certain. It's a fascinating story of the youth of the universe that remains to be written.
A host galaxy rich in heavy elements
The NOEMA interferometer on the Bure plateau, in the French Alps. DiVertiCimes / DiVertiCimes.
A mystery never comes alone, the observations of the galaxy-host at the heart of which rages this distant quasar surprised astronomers. They discovered considerable amounts of dust and carbon, an element considered "heavy" in astronomy, that is to say more complex than the hydrogen or helium formed at the time of the Big Bang. "The dust is also necessarily composed of heavy elements," says Jan Martin Winters, an astronomer at IRAM who made these observations using the NOEMA radio telescope network located on the Bure plateau.
However, according to our knowledge, only the explosions of stars make it possible to form this type of components. "In these very remote times, several generations of stars have had to succeed one another," says Jan Martin Winters. "However, they had to be very numerous, very massive and explode after only a few million years to explain the huge amounts of carbon and dust that we detect." A very important constraint to be taken into account in future models. evolution of our universe.
F I N .
By Tristan Vey & Cyrille Vanlerberghe - Updated on 08/12/2017 at 13:53
Artist's impression of a hypermassive black hole growing from the material. Robin Dienel / Carnegie Institution for Science.
The very existence of this mastodon, 800 million times the mass of our Sun, as early in the history of the universe, is an enigma for astronomers.
He is as big as he is distant, and it is a real surprise. A hypermassive black hole, 800 million times the mass of our Sun, whose light took 13 billion years to reach us, by an international team of researchers (work published in Nature and The Astrophyscial Journal Letters) . It is an absolute distance record for an object of this type (the previous record dates from 2011), but also a weight record for a star as far away. "It is at least ten times larger than the previous supermassive black hole detected at this type of distance," says Bram Venemans, astronomer of the Max Planck Institute for Astronomy in Heidelberg, Germany, who coordinates with his colleague Fabian Walter looking for this type of objects in the confines of the visible universe for several years.
The discovery itself is credited to Magellan telescopes at the Las Campanas observatory in Chile, after a systematic search on a very large number of stars with NASA's WISE space telescope. The black hole was then the subject of intensive observation campaigns with the VLA (New Mexico) and NOEMA radio telescope networks of Iram, located in the French Alps. The latter succeeded in detecting the galaxy in which the mastodon was hiding .
The latter was betrayed by the gargantuan meal he is eating. A disc of matter collapses in fact spiral in the mouth of the cosmic ogre. When falling, this matter heats up and emits a very intense radiation, 40 trillion times brighter than our Sun. This type of black hole surprised in full feast has a name: this is called a quasar. These are among the brightest objects in the universe. There are several tens to discover at such distances, according to some estimates. European space satellites Euclid and American WFIRST will make their daily bread. The future successor of Hubble, the James Webb Space Telescope (JWST), too.
The light emitted by this hypermassive black hole took so long to reach us (more than 13 billion years) that we observe it as it was at a very remote time. In this case, 690 million years only after the Big Bang, less than 5% of the age of the universe. His early childhood in a way. "We were surprised to see that the black hole was so heavy," admits Bram Venemans. "It was really unexpected and it will give us constraints on the evolution of this type of objects in such a young universe."
A voracious embryo of a thousand solar masses?
Patrick Petitjean, astronomer at the Institute of Astrophysics of Paris and quasar specialist, explains that it would take a primordial black hole of a thousand solar masses to form such a mastodon within the time allowed by his young age. But we do not really know how such objects could be formed in the present universe. Stellar black holes, which are formed by the collapse of massive stars at the end of life, weigh at most only a few tens of solar masses. "In these very old times, the universe was denser," says the researcher. "Huge clouds of gas may have collapsed at once to directly form those big black holes of a few thousand solar masses."
These voracious "big embryos" would then have snatched large amounts of surrounding matter in a relatively short time on the astronomical scales to become such obese as greedy. But this scenario, as plausible as it is, is still far from certain. It's a fascinating story of the youth of the universe that remains to be written.
A host galaxy rich in heavy elements
The NOEMA interferometer on the Bure plateau, in the French Alps. DiVertiCimes / DiVertiCimes.
A mystery never comes alone, the observations of the galaxy-host at the heart of which rages this distant quasar surprised astronomers. They discovered considerable amounts of dust and carbon, an element considered "heavy" in astronomy, that is to say more complex than the hydrogen or helium formed at the time of the Big Bang. "The dust is also necessarily composed of heavy elements," says Jan Martin Winters, an astronomer at IRAM who made these observations using the NOEMA radio telescope network located on the Bure plateau.
However, according to our knowledge, only the explosions of stars make it possible to form this type of components. "In these very remote times, several generations of stars have had to succeed one another," says Jan Martin Winters. "However, they had to be very numerous, very massive and explode after only a few million years to explain the huge amounts of carbon and dust that we detect." A very important constraint to be taken into account in future models. evolution of our universe.
F I N .
