Incredible observations from the Very Large Telescope have revealed huge gas reservoirs around some of the earliest galaxies in the universe. The presence of this gas helps explain how galaxies were able to form so many stars and how the first supermassive black holes managed to bulk up very quickly during the cosmic dawn, the first billion years or so of the universe.
As reported in The Astrophysical Journal, the international team looked for a particular type of emission around 31 target quasars (what a galaxy is referred to when it has an active supermassive black hole). Using the sophisticated MUSE instrument, the team was able to identify 12 enormous nebulae enshrining these galaxies, eight of which had never been seen before.
Supermassive black holes and their host galaxies are expected to have grown pretty rapidly, but unfortunately, at the moment, we can only see them when they are already pretty big. Some of these observations highlighted that there was plenty of gas and dust for galaxies to form stars, but not enough to fuel the black hole's growth.
The latest study shows that there’s plenty of fuel for black holes to gobble on. The reservoir of cool gas observed is up to 100,000 light-years across with a mass of more than a billion times that of the Sun. Definitely a hearty meal for the growing supermassive black holes.
“We are now able to demonstrate, for the first time, that primordial galaxies do have enough food in their environments to sustain both the growth of supermassive black holes and vigorous star formation,” lead author Emanuele Paolo Farina, of the Max Planck Institute for Astronomy in Heidelberg, Germany, said in a statement. “This adds a fundamental piece to the puzzle that astronomers are building to picture how cosmic structures formed more than 12 billion years ago.”
The current observational limit that challenges our investigations of the cosmic dawn will soon be broken. Hubble and Spitzer's successor, the James Webb Space Telescope, will launch in 2021 and the Extremely Large Telescope (ELT) will see its first light in 2025.
“With the power of the ELT, we will be able to delve even deeper into the early universe to find many more such gas nebulae,” Farina added.
The mist that once shrouded the infancy of the universe is finally being lifted.