Star formation underway 250 million years after Big Bang

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By establishing the age of MACS1149-JD1, the team has effectively demonstrated the existence of early galaxies to times earlier than those where we can now directly detect them. The universe initially was devoid of elements such as oxygen, carbon and nitrogen, which were first created in the fusion furnaces of the earliest stars and then spewed into interstellar space when these stars reached their explosive deaths.

In addition, ALMA also detected a weaker signal of hydrogen emission was also detected by ESO's Very Large Telescope (VLT).

Crucially, some stars in the ancient galaxy were already "mature", implying they had been around much longer - another 250 million years or so.

Before the first stars kicked on, the universe was a relatively boring place, consisting primarily of radiation leftover from the Big Bang, as well as hydrogen and helium.

The distance of the faraway galaxy was calculated using ground-based telescopes in Chile and infrared data from orbiting telescopes, to reconstruct the early history of MACS1149-JD1. That gives us an indication of how much earlier in the history of the Universe - which we can't now probe with our telescopes - that this object actually formed. The presence of oxygen is a clear sign that there must have been even earlier generations of stars in this galaxy. This period, commonly referred to as "cosmic dawn, ' is of particular interest because it marked the transition from a hot, dense, and almost homogeneous universe to the universe we are more familiar with today - one filled with stars, planets, nebulae, and people". The MACS1149-JD1 observation shows galaxies must have existed before any that are now detectable.

A group of researchers has reportedly detected oxygen in a far-off galaxy, which is near about thirteen billion light-years away from our planet. This reflects both the competitive and collaborative nature of forefront of scientific research.

"Prior to our study, there were only theoretical predictions of the earliest star formation". "We are eager to find oxygen in even farther parts of the universe and expand the horizon of human knowledge".

"With these observations, we are pushing back the limit of the observable universe and, therefore, we are coming closer to the cosmic dawn", University College London astronomer Nicolas Laporte said, adding that computer simulations suggest that the first stars appeared about 150-million years after the Big Bang.

The Atacama Large Millimeter/submillimeter Array (ALMA), an global astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile.

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

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