A Discovery Near the Dawn of the Time Has Revealed Something Fundamental About the Universe

An international team of researchers has uncovered first-of-its-kind evidence from near the beginning of the universe that helps resolve a fundamental question about the cosmos. 

The researchers reported collecting the first evidence that an outpouring of gas from some of the brightest and most powerful objects in the universe can curb new stars from forming. The finding adds to our fundamental understanding of how stars and galaxies came into being in the celestial moments after the dawn of time.   

They observed this star-suppressing phenomenon using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, and reported the findings in The Astrophysical Journal. 

The research focussed on a quasar—a super dense region of space powered by a supermassive black hole—called J2054-0005. This particular quasar is moving away from Earth at tremendous speeds in a region of space when the universe was less than a billion years old. 

They used ALMA to show how molecular gas—the stuff stars feed on to form—pours out from the quasar. It’s these powerful outflows that push molecular gas out into space faster than potential stars can use it, thereby suppressing their birth.

“Quasars are especially energetic sources, so we expected that they may be able to generate powerful outflows,” said study co-author, observational astronomer Dragan Salak, in a press release.

Astrophysicists have previously theorized that quasars might quash the ability for stars to form and therefore influence the evolution of galaxies. Other studies have provided more indirect evidence of this too, such as observing ionized gas pouring out of quasars that represent a more recent cosmic age. 

“Even if ionized gas is outflowing, it is not direct evidence that star formation will be immediately affected, because star formation requires molecular gas,” Salak told Motherboard in an email. He said their work is the first “strong direct evidence”.

Detecting this torrent of molecular gas required measuring how the stream absorbed radiation coming out of the quasar. “We can observe a very bright source of light—microwave radiation in this case—such as a quasar. If the space between that light source and us is empty, we would see all the light coming out of the quasar. However, if we see that light at some specific wavelengths is missing, something must have absorbed it on the way from the light source to us,” explained Salak. Specific wavelengths correspond to different footprints of molecular gas pouring out of the quasar, and these footprints are what ALMA picked up. 

The way stars and galaxies form is a complex dance, and black holes can either promote or hinder those processes. Scientists are constantly testing theories, and uncovering new evidence, of how this works. As their ability to image distant objects, like J2054-0005, gets better, more evidence will be revealed.