Azernews.Az

by Alimat Aliyeva

Astronomers have created the most detailed map of the Universe in history. The project was carried out over five years using the Dark Energy Spectroscopic Instrument (DESI), which surveys the night sky in unprecedented detail. The resulting dataset includes more than 47 million galaxies and quasars—nearly ten times more than in previous large-scale cosmic maps, AzerNEWS reports.

The instrument, installed at the Kitt Peak National Observatory in Arizona, began observations in 2021. Initially, researchers expected to catalog around 34 million objects, but the system exceeded expectations. Some of the most distant galaxies were detected using only 100–200 photons, highlighting the extraordinary sensitivity of the instrument.

“Throughout my career, we’ve followed a trend where every decade the maps become about ten times larger,” said David Schlegel of the Lawrence Berkeley National Laboratory. He added that if this trend continues, by 2061 it may be possible to map every observable galaxy within a radius of 10 billion light-years.

The current map covers about 14,000 square degrees of the sky, with plans to expand the coverage to 17,000. In total, the entire sky spans more than 41,000 square degrees, although large portions are obscured by bright foreground objects such as the Milky Way.

Although the main observational phase has been completed, scientists will continue analyzing the massive dataset for at least another year before making it fully available to the global scientific community. The instrument itself is expected to keep operating until the end of 2026, and with upgrades, it could remain active into the 2030s.

Interestingly, astronomers note that datasets like this are not just maps but also “time machines” in a sense: because light takes billions of years to reach us, we are effectively seeing galaxies as they were in the distant past. This allows scientists to study how the Universe evolved over cosmic time and may even help refine our understanding of dark energy—the mysterious force driving the accelerated expansion of the Universe.