Scientist carried out high-sensitivity observations with ALMA and discovered light from ionised oxygen in SXDF-NB1006-2, making this the most distant unambiguous detection of oxygen ever discovered.
Oxygen in SXDF-NB1006-2 was found to be ten times less abundant than it is in the Sun.
This galaxy — which we're observing as it was just 700 million years after the birth of the universe.
The astronomers did not discover the oxygen in mass amounts. “The small abundance is expected because the Universe was still young and had a short history of star formation at that time,” Naoki Yoshida, of the University of Tokyo, said in a statement.
“Studying heavy elements also gives us a hint to understand how the galaxies were formed and what caused the cosmic reionization.” said Inoue.
Previous study implies that, after the universe was born in the Big Bang about 13.8 billion years ago the universe was too hot that all of the atoms that existed were separated into positively charged nuclei and negatively charged electrons.
SXDF-NB1006-2,would have been a prototype of the sources responsible for reionization. The young galaxy is also considered to have very little un-ionised hydrogen gas, and only a small amount of dust, which is made up of heavy elements.
“Something unusual may be happening in this galaxy . I suspect that almost all the gas is highly ionised,” Inoue said.
The study was published in the journal Science.
