Astronomers at the University of Arizona discovered a quasar at a record distance: about 13.03 billion light-years from Earth. It was formed only 670 million years after the Big Bang, and is the site of a challenging supermassive black hole whose mass is equivalent to 1.6 billion suns.
One Quasar (Abbreviation of radio source CUASistelAR) is a very luminous galactic core with a Supermassive black hole The interior is surrounded by a gaseous accretion disk. When the gas falls into the hole, a large amount of energy is released in the form of radiation, which can be observed in the entire electromagnetic spectrum.
Quasars are one of the brightest sources in the universe and are usually brighter than their own host galaxies.To calculate its distance, astronomers looked at the so-called Redshift The data in the range allows you to go back in time and see how many years they have been formed after the Big Bang.
Until now, records have been made by Front sight J1342 + 0928The redshift of is 7.54, which corresponds to the universe 690 million years ago, but now scientists from the University of Arizona (USA) have observed another quasar called J0313-1806It was born about 20 million years ago, when the universe was almost 5% of its current age.
“The redshift of quasar J0313-1806 is 7.642, which corresponds only to 670 million years after the Big Bang“, explain to Sinc the lead author of the study, Feige Wang, Is a researcher at the Steward Observatory of the University of Arizona. Therefore, it is the oldest known, and is said to be the most remote.It is located 13.003 million light-years from Earth.
Discovery team will be in Astrophysical Journal Letter But this week, he has already introduced them at the 237th meeting of the American Astronomical Society, which is actually being held.
Black hole that violates the theory
Except the farthest Wang Three other key points of this quasar are highlighted: supermassive black holes (also known as the oldest or most distant black holes), the “wind” jets it emits, and the high rate of star formation in galaxies.
He clarified, “The first thing is that it contains a supermassive black hole (SMBH in English) with a size of 1.6 billion solar mass, About twice that of J1342 + 0928. The existence of this large-scale SMBH requires a seed black hole with a solar mass of more than 10,000, which challenges the theory of the formation of these objects, although their findings have helped limit the possibilities envisaged so far.
Another author, professor Xiaohui FanExplains: “We think there is a mechanism that involves a large amount of cold primordial hydrogen directly collapsing into the seed black hole, without the need for intact stars as raw materials (some models point out). This is the only reason this will make the quasar J0313 The supermassive black hole of -1806 grew to 1.6 billion solar masses in such an early universe, which is what makes the new quasar record so valuable.”
Extremely high wind speed
“Another key point is that it has a jet of (super-hot gas and plasma) ejecting from the quasar at a very fast speed. The wind travels at 20% of the speed of lightIt is the first evidence of such “feedback” in such an early quasar in the universe,” Wang said.
By measuring the luminosity of J0313-1806, his team calculated that the big black hole at its center is absorbing about 25 suns each year, which is the main reason why the hot plasma wind blows to the surrounding galaxies. The speed of relativity. For comparison, the black hole at the center of the Milky Way has almost no activity.
High star formation rate
At last, galaxy The place that contains the quasar also has a related feature: it is forming new stars at a certain speed 200 times higher than our Milky Way, The amount of light emitted is a thousand times less, and the mass of the sun produced every year is about one.
Wang said: “The relatively high rate of star formation, similar to that seen in other quasars of similar age, tells us that the host galaxy is growing very fast.”
Fan added: “In addition, these quasars may still be in the process of establishing their supermassive black holes.” “Over time, the exit jets of the quasars heat up and push all the gas out of the Milky Way. Then, the black holes are no longer. If any matter continues to feed, it will stop growing. This is evidence of how this matter grows. First of all, huge galaxies and their quasars.”
The co-authors said the researchers hope to find more quasars in the same period, including potential new records. Jinyi that, and also Steward Observatory. Yang and Fan made observations at the 6.5-meter Magellan Baade ground telescope at the Las Campanas Observatory in Chile on the night of the discovery of J0313-1806.
The team of astronomers will continue to make new observations and hope to discover more secrets of new quasars in the future. James Webb Space Telescope It is scheduled to be launched into space at the end of 2021.