A group of space scientists from different countries has discovered a possible indication of gas material recycling by observing a gas cloud stream heading towards a massive galaxy. According to their study published in the journal Science, the scientists have examined a gas cloud surrounding a dense galaxy cluster located 11 billion light years away and obtained insights from their research.
For many years, scientists have predicted that enriched gases surrounding galaxies could be pulled into these galaxies and be used to create new stars. They have also theorized that these gases could have been produced by supernova explosions that escape their galaxy, and when they are pulled back into a galaxy, they are being recycled. The researchers believe that they have now found evidence of such recycling.
To investigate this phenomenon, the scientists studied data from the Subaru and Keck II telescopes, which were focused on a huge galaxy at redshift 2.3, surrounded by a nebula known as MAMMOTH-1. When the nebula was discovered in 2017, it was considered to be enigmatic. However, the new examination suggests that the galaxy is pulling material from the nebula closer through three distinct gas streams. Two of the streams point to a single quasar, which the scientists suspect resides in the galaxy.
Further analysis of the streams revealed that they contain a lot of carbon, in addition to hydrogen and helium, which previous research has shown is created inside of stars. Therefore, the carbon in the gas stream must have once existed in a star, but it no longer does, hinting at expulsion due to a supernova. The fact that the gas in which the carbon exists is part of a stream heading into the galaxy suggests that it will soon be used to form new stars.
The scientists also conducted kinematic modeling of the galaxy and nebula, which showed that the gas streams are spiraling into the galaxy, indicating that they are likely part of a massive recycling process, where stars explode and leftover material from the explosions is used to construct new stars.