Observations by the Chilean ALMA Telescope show that the distant ID2299 galaxy discharges almost half of the gas used to form stars at an alarming rate: about 10,000 solar masses per year. Astronomers believe that this spectacular event was triggered by a collision with another galaxy, which made us rethink how they stopped forming stars and where they emit fuel to produce new stars.
When galaxies stop forming stars, they begin to “die”, but until now, it has not been clearly observed how this process started in distant galaxies.
use Atacama Large Millimeter/Submillimeter Array (ALMA)Astronomers noticed that the European Southern Observatory (ESO) and other partners are in Chile Galaxy ID2299.So far, its light has consumed some 9 billion years Reaching us: We saw it when the universe was only 4.5 billion years old (approximately 13,800 years today).
But what attracted the attention of this galaxy is that it is expelling almost half of the cold stars producing gas, namely 46% Specifically, at an alarming rate of 10,000 solar masses per year, that is equivalent to the time required to generate 10,000 suns per year.
Because the Milky Way is still forming stars very rapidly (hundreds of times faster than our Milky Way), the remaining gas will be quickly consumed, causing ID2299 to cease production within tens of millions of years.
He said: “This is the first time we have observed a typical huge star-forming galaxy in the distant universe, which will be’dead’ due to a large amount of cold gas ejection.” Annagracia Puglisi, The principal investigator of this new study comes from Durham University and Thackeray Nuclear Research Center (CEA- Thackeray, France).
According to the team, the event that caused the huge gas leak was a collision between two galaxies, which eventually merged into ID2299. The elusive clue that led scientists to think of this situation is that the exhausted gas is related to the so-calledUmi‘.
The tidal tail is a slender stream of gas and stars that extend into interstellar space as a result of the merger of two galaxies. It is difficult to see them in distant galaxies because they are usually too faint. However, the research team managed to observe this relatively bright phenomenon as if it were launched into space, and was able to recognize it as a tidal tail.
The third way to get stellar material
Most astronomers think Wind caused by star formation with Black hole activity At the center of the massive galaxy, they are responsible for launching star-forming material into space, thus terminating the Milky Way’s ability to create new stars.
However, this new study was published in the journal this week Natural astronomy, Indicating that the merger of the Milky Way may also be the cause of expelling the fuel needed for star formation to space.
The co-author of the study said: “Our research shows that gas ejection may be caused by merging, and wind and tidal tails may look very similar.” Emanuele Daddi, Located in the center of CEA-Saclay.
Looking back at how the galaxy died
Therefore, some scientists who previously identified wind in distant galaxies may have actually observed tidal tails ejecting gas from these galaxies. Duddy admitted: “This may change our understanding of the “death” of galaxies.”
Surprisingly, the death process of a distant colliding galaxy was discovered, and at the same time it lost its ability to form stars. accidental. When using ALMA to study the characteristics of air-conditioning in more than 100 distant galaxies, a powerful observatory made it possible to collect enough data within a few minutes to detect ID2299 and its jet tail.
“ALMA provides new ideas for the mechanism of preventing the formation of stars in distant galaxies. Witnessing such a large-scale destructive event together adds significance to the complex puzzle of galaxy evolution.” Chiara Circosta, Researcher at University College London, UK.
In the future, the research team can use ALMA to make deeper and higher-resolution observations of the galaxy, so that they can better understand the dynamics of the discharged gas. In addition, the data observed from ESO’s future ultra-large telescopes can enable us to explore the connection between stars and gas in ID2299, thereby providing new ideas for the evolution of galaxies.
Annagrazia Puglisi et al. “From a huge starburst galaxy, at z = 1.4, a Titanic interstellar medium ejection occurred.” Natural astronomy, 2021