A cosmic telescope zooms to the beginning of time

A cosmic telescope zooms to the beginning of time

Observations from the Gemini Observatory (United States) have identified a key footprint of an extremely distant quasar, allowing astronomers Take samples of the light emitted since the dawn of time. Astronomers discovered this deep glimpse of space and time thanks to an uncomplicated close-up galaxy that acted like a gravitational lens, magnifying the ancient light of the quasar, reports Europa Press.

The Gemini observations provide critical pieces of the puzzle to confirm this object as the quasar of the brightest appearance so early in the history of the Universe, which It increases the hope that more sources like this one will be found. Before the cosmos reached its trillionth birthday, part of the first cosmic light began a long journey through the expanding Universe. A particular light beam, coming from an energy source called a quasar, accidentally passed near an intermediate galaxy whose gravity bent and magnified the light of the quasar and refocused it in our direction, allowing telescopes like the Gemini of the North to explore the quasar in great detail.

"If it were not for this improvised cosmic telescope, the light of the quasar would appear 50 times fainter," said Xiaohui Fan, from the University of Arizona, who led the study. This discovery shows that there are quasars with gravitational lenses despite the fact that we have been searching for more than 20 years and have not found others so far in time. " Gemini's observations provided key pieces of the puzzle by filling a critical hole in the data. The Gemini North telescope in Maunakea, Hawaii, used the near-infrared Gemini spectrograph (GNIRS) to dissect a significant swath of the infrared part of the light spectrum. The Gemini data contained the magnesium revealing signature, which is critical to determining how long ago we are looking.

From the time of the first light of the Big Bang

The observations of Gemini also led to a determination of the mass of the black hole that feeds the quasar. "When we combined the Gemini data with observations from multiple observatories in Maunakea, the Hubble Space Telescope and other observatories around the world, we were able to paint a complete picture of the quasar and the intermediate galaxy," says Feige Wang of the University of California, Santa Bárbara (United States), who is a member of the discovery team. That image reveals that the quasar is located far back in time and space, shortly after what is known as the Time of Reionization, when the first light emerged from the Big Bang. "This is one of the first bright sources when the Universe emerged from cosmic dark ages," says Jinyi Yang of the University of Arizona, another member of the team. "Before this, no stars, quasars or galaxies had formed, until objects like this appeared as candles in the dark," he adds.

The foreground galaxy that improves our vision of the quasar is especially tenuous, which is extremely fortuitous. "If this galaxy were much brighter, we would not have been able to differentiate it from the quasar," Fan says, adding that this finding will change the way astronomers will look for quasars with lenses in the future and could significantly increase the number of lens discoveries. quasar. However, Fan suggests: "We do not expect to find many quasars brighter than this throughout the observable Universe."

Composed of dust and gas

The intense brightness of the quasar, known as J0439 + 1634 (J0439 + 1634 for short), also suggests that it is powered by a supermassive black hole in the heart of a young galaxy in formation. The wide appearance of the magnesium imprint captured by Gemini allowed astronomers to measure the mass of the supermassive black hole of the quasar 700 million times that of the Sun.

The supermassive black hole is probably surrounded by a flattened disk of dust and gas. This ring of matter, known as the accretion disk, is very likely to continue turning inward to feed the power station of the black hole.

The submillimeter wavelength observations with the James Clerk Maxwell Telescope in Maunakea suggest that the black hole is not only accumulating gas, but that it can cause the birth of stars at a prodigious rate, which seems to be up to 10,000 stars per year. In comparison, our Galaxy Milky Way generates one star per year. However, due to the increased effect of gravitational lenses, the actual speed of star formation could be much lower.

Quasars are extremely energetic sources fed by huge black holes that are believed to have resided in the first galaxies that formed in the Universe. Because of their brightness and distance, quasars provide a unique view of conditions in the early Universe. This quasar has a red shift of 6.51, which translates to a distance of 12.8 billion light years, and seems to shine with a combined light of about 600 trillion suns, driven by the enlargement of the gravitational lens. The foreground galaxy that curved the light of the quasar is approximately half of that distance, only 6,000 million light years from us.



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