First Galaxies tagged posts

Water may have first formed 100–200 million years after the Big Bang, according to a modeling paper published in Nature Astronomy. The authors suggest that the formation of water may have occurred in the universe earlier than previously thought and may have been a key constituent of the first galaxies.

Water is crucial for life as we know it, and its components—hydrogen and oxygen—are known to have formed in different ways. Lighter chemical elements such as hydrogen, helium and lithium were forged in the Big Bang, but heavier elements, such as oxygen, are the result of nuclear reactions within stars or supernova explosions. As such, it is unclear when water began to form in the universe.

Researcher Daniel Whalen and colleagues utilized computer models of two supernovae—the...

Researchers have been able to make some key determinations about the first galaxies to exist, in one of the first astrophysical studies of the period in the early Universe when the first stars and galaxies formed, known as the cosmic dawn.

Using data from India’s SARAS3 radio telescope, researchers led by the University of Cambridge were able to look at the very early Universe — just 200 million years after the Big Bang — and place limits on the mass and energy output of the first stars and galaxies.

Counterintuitively, the researchers were able to place these limits on the earliest galaxies by not finding the signal they had been looking for, known as the 21-centimetre hydrogen line.

This non-detectio...