Its faint light has taken so long to reach Earth that its journey began just 500 million years after the Big Bang - the cataclysmic event that brought the cosmos into being.
An worldwide team of researchers from University College London and Osaka Sangyo University in Japan published a paper in the journal Nature showing that stars in the MACS1149-JD1 galaxy formed 250 million years after the Big Bang.
"I am sure that the future combination of ALMA and the James Webb Space Telescope will play an even greater role in our exploration of the first generation of stars and galaxies", said Zheng.
This image shows the galaxy cluster MACS J1149.5+2223 taken with the NASA/ESA Hubble Space Telescope; the inset image is the very distant galaxy MACS1149-JD1, seen as it was 13.3 billion years ago and observed with ALMA. The massive newborn stars in the second burst ionized the oxygen between the stars; it is those emissions that have been detected with ALMA. They detected a signal from ionised oxygen whose infrared light was stretched ten-fold to microwave wavelengths by the expansion of the Universe.
They trained the Atacama Large Millimetre/submillimetre Array (ALMA) in Chile on one of the farthest known objects in the Universe, a galaxy named MACS1149-JD1.
The real breakthrough was the detection of oxygen in the galaxy, which is observable in the Leo constellation, though not with the naked eye.
An global team of astronomers led by Hashimoto used ALMA to observe a distant galaxy called MACS1149-JD1.
"The mature stellar population in MACS1149-JD1 implies that stars were forming back to even earlier times, beyond what we can now see with our telescopes", said Nicolas Laporte, a researcher at University College London/Université de Toulouse and a member of the research team, in a statement.
'We are therefore able to use this galaxy to probe into an earlier, completely uncharted, period of cosmic history'. This is the first time that astronomers have detected stars that are that old.
Although the presence of galaxies at this epoch is not necessarily surprising, the detection of oxygen in MACS1149-JD1 indicates a more remarkable conclusion. Referencing infrared observations, the team determined that star formation in the galaxy started at an unexpectedly early stage; 250 million years after the Big Bang. By establishing the age of MACS1149-JD1, the team has effectively demonstrated that galaxies existed earlier than those we can now directly detect.
Co-author Professor Richard Ellis, also from UCL, said: "Determining when cosmic dawn occurred is akin to the Holy Grail of cosmology and galaxy formation". There is renewed optimism we are getting closer and closer to witnessing directly the birth of starlight.
'Since we are all made of processed stellar material, this is really finding our own origins'.
ALMA has set the record for the most distant oxygen several times. ALMA has been used previously to break the record for the most distant known galaxy, it did so twice in 2016 finding galaxies 13.1 billion light-years away, and 13.2 billion light-years away. Several months later, Nicolas Laporte of University College London used ALMA to detect oxygen at 13.2 billion light-years away.