Subaru astronomers find distant protocluster of galaxies

Astronomers using a Hawaii Island telescope reported the discovery of one of the most distant protocluster of galaxies yet found.

The protocluster’s distance places it as existing less than 1 billion years after the Big Bang, Subaru Telescope officials said.

“You’re going back about as far as you can go,” Subaru outreach officer Suzanne Frayser said. Studying light “is like you’re in a time machine in some ways.”

Jun Toshikawa, of Japan’s The Graduate University for Advanced Studies, Noburnari Kashikawa, of the National Astronomical Observatory of Japan, and Kyoto University’s Kazuaki Ota made the discovery. The finding is important, telescope officials said, because protoclusters are ancestors of today’s massive clusters of galaxies, and the protocluster discovery provides insight into scientists’ understanding of how large-scale structures form and galaxies evolve.

They confirmed the protocluster existed 12.72 billion years ago.

Scientists said understanding how clusters form is an important step in addressing issues of structure formation and galaxy evolution.

“A necessary part of this process is an investigation of all stages of cluster formation from beginning to end, which is why the current team gave particular emphasis to studying the birth of clusters,” a Subaru news release about the discovery read. “Astronomers think that the Universe started out as an almost homogeneous mass that spread uniformly. Small fluctuations in the initial mass distribution increased by gravity over the 13.7 billion years of the Universe’s age and produced the recent array of clusters. Because clusters contain a larger number of old and massive galaxies than those found in isolated galaxies, astronomers speculate that developing clusters may significantly affect the evolution of their member galaxies.”