They discovered the oldest quasars in the universe: what this discovery means for science

One of the primary goals of modern astronomy today is to find and observe the most distant and oldest objects in the universe.

He announced this week that thanks Gemini North Large Telescope It is located on Maunakea Island in Hawaii, USA, and astronomers were able to discover it A pair of merging quasars was seen only 900 million years ago after the Big Bang. The big bang that started everything we know so far.

The observatory, which takes advantage of the wonderful weather conditions of the dormant Maunakea volcano, which lies at an altitude of 4,214 metres, was the place to find it. The most distant pair of merging quasars ever found. And also the first of the period known as Cosmic dawn.

The cosmic dawn is an extended space-time From about 50 million years to 1 billion years immediately after the Big Bang. In that key era, the first stars and galaxies appeared, filling the dark universe with light for the first time, and beginning the beginning of the universe. Reionization eraThis is the period during which ultraviolet light from the first stars, galaxies, and quasars spread throughout the universe, ionizing the intergalactic medium and stripping primitive hydrogen atoms of their electrons.

This era of reionization was a It was very important in the history of the universe because it marked the end of the cosmic Dark Ages, Where the great structures we observe today in our world were born. To understand the precise role quasars played during the Era of Reionization, astronomers search for and study these objects at cosmic dawn, in these early ages of the universe.

According to astrological terminology, A Quasar also quasar, It is an abbreviation for what is defined as a quastellar radio source, To abbreviate it in English. In this way, quasars form when the black hole at the center of the galaxy begins to “swallow” all the matter surrounding it.

In this process that Accretion disk around a black holeall the massive matter surrounding it rushes towards its center in a way similar to the way water escapes from a pond.

“The statistical properties of quasars in the era of reionization tell us many things, such as the progression and origin of reionizationSupermassive black holes form during cosmic dawn “The oldest evolution of quasar host galaxies,” said Yoshiki Matsuke, an astronomer at Ehime University in Japan and lead author of the paper describing these findings. published in “The Astrophysical Journal Letters”.

“So far, about 300 quasars from this period have been discovered, but they have never been discovered in pairs. This discovery was 'pure coincidence,' Matsuoka said, adding that while reviewing images taken with the camera Hyper Supreme Cam Follower Subaru telescopeA faint red spot caught his eye, so the discovery of the double object was pure coincidence.

Initially, the team wasn't sure they were a pair of quasars, since distant quasar filters are contaminated by many other sources, such as stars, foreground galaxies, and gravitational lensing effects. So, to confirm this finding, the team used spectrometers Subaru telescopes and Gemini North, Breaking down light emitted by quasars into its component wavelengths.

Thus, the team performed follow-up spectroscopy using the Faint Object Camera and Spectrograph (FOCAS) on the Subaru telescope and the Gemini Near-Infrared Spectrometer (GNIRS) on Gemini North. Spectra obtained using GNIRS, which Decomposition of light emitted by a source into its wavelengths Of which it is composed, it was very important in determining the nature of the pair of quasars and their host galaxies.

“What we have learned from GNIRS observations is that quasars are too faint to be detected in the near infrared, even with one of the largest telescopes on Earth,” Matsuoka noted.

The spectra found by the team of experts allowed us to estimate that part of the light detected in the optical range comes from star formation. Ongoing quasars in host galaxies. In addition, they discovered that both black holes are massive, with a mass 100 million times the mass of the Sun, and a bridge of gas extending between the quasars indicates a large-scale merger.

“The existence of merging quasars in the epoch of reionization has been expected for a long time. This has now been confirmed for the first time,” concluded Matsuoka. “This discovery links the early formation of cosmic structure to the complex universe we observe billions of years later.”

Study these distant objects It provides valuable information about the process of reionization and the formation of the first objects in the universeAnd so are these quasars.

Astronomers believe there may be more discoveries like this in the near future, using the NSF-DOE Vera C. Rubin Observatory's Legacy Survey of Space and Time (LSST) which will be completed in 2025 and is scheduled to discover millions of quasars using His observatory. Deep imaging capabilities.