A trove of molecules has been unearthed in two galaxies that we see as they existed more than 12 billion years ago, revealing information about how ancient realms formed stars.

There is a currently producing quasar in one of the distant galaxies, APM 08279+5255. The Milky Way galaxy is absorbing huge amounts of gas at an incredible rate, with hundreds of times more stars than stars in its core – the other galaxy, NCv1 .143, is a more “normal” galaxy. However, both can be seen to form a supermassive black hole (an active black hole).

These two galaxies were targeted by astronomers using the Northern Extended Millimeter Array NOEMA in France. NOEMA is capable of detecting millimeter and submillimeter radio waves. Interestingly, a team led by Chentao Yang from Chalmers University of Technology in Sweden detected emission from 13 different molecules in these two galaxies.

“We see a part of the electromagnetic spectrum that is difficult to observe in nearby galaxies,” Yang said in a press release. “But due to the expansion of the universe, the light from distant galaxies like this is shifting towards longer wavelengths that we can see with observing radio telescopes.” [на] submillimeter [довжини хвилі].”

The discovery constitutes the largest collection of molecules ever found in galaxies at such great distances (the galaxies are currently about 20 billion light-years away and further away due to cosmic expansion).

The 13 different types of molecules detected include carbon monoxide, carbon monosulfide, cyano radical (a radical is a molecule that has an unpaired electron in the outer shell of one of its constituent atoms), formyl cation (a cation is a positively charged ion). , hydrogen cyanide, hydrogen isocyanide, oxide nitrogen and water. Young’s team also discovered five molecules not previously found in the early universe: cyclopropenylidene (a highly active organic molecule also found on Saturn’s moon Titan), diazenylium (consisting of molecular nitrogen and a hydrogen ion), the organic molecule ethynyldene radicals, and hydronium ions (consisting of a water molecule and a hydrogen ion) and methidine radicals (a highly active organic molecule).

All of these molecules are commonly found in the interstellar gas in our Milky Way galaxy, and each provides clues about the environment in which they exist—the environment in which we see many stars forming.

“We knew that these galaxies were incredible star factories, possibly some of the largest galaxies the universe has ever seen,” Yang said.

The team also found that the quasar in APM 08279+5255 contains more excited molecular gas with higher temperature and density than NCv1.143 as a whole, likely due to activity around the black quasar. hole. Its molecular content is similar to galaxies with active black holes in the more modern universe. Similarly, NCv1.143’s molecular inventory resembles local starburst galaxies, which are simple galaxies from which many stars are born, such as the Cigar Galaxy (Messier 82) in the Big Dipper constellation Ursa Major. It seems that the chemical composition of such galaxies already existed 12 billion years ago.

But not everything is the same. The strength of the emission of certain molecules, such as carbon dioxide, combined with the extreme conditions in the star-forming gas of the two galaxies, suggests what is called a “top heavy initial mass function.” The initial mass function, or IMF, describes how many stars of a given mass can form; low-mass stars are much more common than high-mass stars. A large IMF means that more massive stars could have formed in the early universe than today. This not only explains why galaxies in the early universe detected by the James Webb Space Telescope are brighter than expected (they contain more massive, brighter stars), but it also suggests the existence of more massive stars exploding as supernovae, which would accelerate the chemistry. In these galaxies, heavy elements are dispersed into space

“The most prominent galaxies in the early universe were finally able to tell their stories through their molecules,” said co-author Pierre Cox of Sorbonne University in France.