Two dense clumps of galaxies discovered billions of light years away from Earth are raising questions about the way astronomers think about the formation of galaxies in the universe.
Two international teams of scientists discovered separate dense groupings of at least 10 and 14 galaxies some 12.4 billion light years away from Earth, and each these groupings are on the verge of forming colossal galaxy clusters.
The studies showed that the forming galaxy clusters had an unusual structure and that their light originated much earlier than expected - only 1.5 billion years after the Big Bang, according to the European Southern Observatory.
The research was first published on Wednesday in two separate papers in the journals Nature and Astrophysical Journal.
In one of the forming clusters, the scientists found that each of the galaxies is forming stars 50 to 1000 times more quickly than the Milky Way.
The total mass of the galaxies in that cluster is approximately 10 trillion times larger than the sun, and according to the scientists, "could be building one of the most massive structures in the universe today."
"How this assembly of galaxies got so big so fast is a mystery," said Yale doctoral candidate Tim Miller, the lead author of one of the papers.
"It wasn't built up gradually over billions of years, as astronomers might expect. This discovery provides a great opportunity to study how massive galaxies came together to build enormous galaxy clusters."
