A group of international astronomers has just made a momentous discovery. The study, published in the Astrophysical Journal, describes the sighting of the most distant object ever, some 13.5 billion light years away. An accompanying article in the journal Monthly Notices of the Royal Astronomical Society Letters, speculated what the object, a galaxy, may be like.
Naming the galaxy HD-1, the scientists proposed two hypotheses. First, the galaxy could be creating stars at breakneck speed, possibly even Population III stars, the universe’s first stars. Secondly, the scientists suggest that HD-1 could be a massive blackhole, roughly 100 million times the mass of the sun.
Fabio Pacucci is the lead author of the MNRAS study, co-author in the discovery paper on ApJ, and an astronomer at the Harvard-Smithsonian Center for Astrophysics.
“Answering questions about the nature of a source so far away can be challenging,” said Fabio Pacucci. “It’s like guessing the nationality of a ship from the flag it flies, while being faraway ashore, with the vessel in the middle of a gale and dense fog. One can maybe see some colors and shapes of the flag, but not in their entirety. It’s ultimately a long game of analysis and exclusion of implausible scenarios.”
The amount of ultraviolet light means that “some energetic processes are occurring there or, better yet, did occur some billions of years ago,” explained Pacucci.
Initially, the scientists suspected that HD-1 was a normal starburst galaxy, which creates stars at a fast pace. However, the sheer number of stars being created – 100 every year, is 10 times higher than the normal rate. This suggests something more primeval.
“The very first population of stars that formed in the universe were more massive, more luminous and hotter than modern stars,” said Pacucci. “If we assume the stars produced in HD1 are these first, or Population III, stars, then its properties could be explained more easily. In fact, Population III stars are capable of producing more UV light than normal stars, which could clarify the extreme ultraviolet luminosity of HD1.”
The supermassive blackhole also fits the evidence, even as a blackhole sucks in even light, photons are emitted around the blackhole itself. Further research is needed for the scientists to confirm exactly what’s going on.
By Zach Fitzner, Earth.com Staff Writer