NASA's Hubble Space Telescope Uncovers Largest Known Population of Star Clusters

NASA's Hubble Space Telescope recently discovered the largest known population of globular star clusters, approximately 16,000 in number.

Scientists have been studying globular star clusters for quite some time now in order to get a better understanding of early formation of stars that later led to the formation of galaxies. NASA's Hubble Space Telescope has been instrumental in helping scientists uncover previously unknown truths and facts about outer space.

In one such discovery, Hubble successfully uncovered the largest known population of globular star clusters, approximately 16,000 in number. For comparison, the Earth's Milky Way is known to house 150 globular star clusters. These clusters are said to be the homesteaders of galaxies and contain some of the oldest surviving stars. Almost all globular star clusters formed within the first 1 billion or 2 billion years after our universe was born in the big bang 13.8 billion years ago.

The newly discovered population is twice as large as any other population of globular star clusters currently known. Not just that, this observation also won Hubble the record for the farthest such systems ever studied, at 2.25 billion light-years away. Most of these globular clusters formed near the center of the galaxy cluster.

"In our study of Abell 1689, we show how the relationship between globular clusters and dark matter depends on the distance from the galaxy cluster's center," explained team member Karla Alamo-Martinez of the Center for Radio Astronomy in a press statement. "In other words, if you know how many globular clusters are within a certain distance, we can give you an estimate of the amount of dark matter."

This dark matter is invisible but is believed to act like a temporary platform upon while stars and galaxies are built. Studying this dark matter can help scientists understand how galaxies and galaxy clusters assembled billions of years ago.

"The globular clusters are fossils of the earliest star formation in Abell 1689, and our work shows they were very efficient in forming in the denser regions of dark matter near the center of the galaxy cluster," lead author John Blakeslee said. "Our findings are consistent with studies of globular clusters in other galaxy clusters, but extend our knowledge to regions of higher dark matter density."

Researchers went on to use Hubble's Advanced Camera for Surveys to look deep inside the heart of Abell 1689, detecting the visible-light glow of 10,000 globular clusters. The team estimated that these 160,000 globular clusters were grouped within a diameter of 2.4 million light-years.