Dark Energy Spectroscopic Instrument Accurately Maps Galaxy Positions Over Time to Help Scientists Better Understand Dark Energy
The most detailed 3D map of the universe to date, showing the location of 7.5 million galaxies, has been released by the cosmic survey project Dark Energy Spectroscopic Instrument (DESI).
The map, released Thursday by Lawrence Berkeley National Laboratory, which leads the project, is the result of DESI’s first seven months of operation.
Each point in the image represents an individual galaxy, made up of 100 to 1,000 billion stars. The map shows the view from Earth five billion light-years towards the constellation Virgo, slowly moving towards the constellation Bootes.
“There’s a lot of beauty in there” said Julien Guy, an astrophysicist at the Berkeley lab. “In the distribution of galaxies on the 3D map, there are huge clusters, filaments and voids. They are the largest structures in the universe. But within them you find an imprint of the very first universe, and the story of its expansion since then.
This is just the beginning of DESI’s work, as the project aims to add more than a million new galaxies to the map each month. When completed in 2026, the map is expected to include more than 35 million galaxies, providing astronomers with a vast array of data to study.
DESI is an advanced detector attached to the four-meter Nicholas U. Mayall Telescope at Kitt Peak in Arizona. Comprised of 5,000 optical fibers, precisely positioned to within 10 microns, it captures glimpses of light coming from space to Earth, covering more than a third of the entire sky.
The detector looks for ripples in the distribution of galaxies known as baryon acoustic oscillations, which became embedded in the distribution of matter during the first hundreds of thousands of years after the Big Bang.
A mysterious ‘ghost’ particle of dark matter may have finally been detected, ending a decades-long search
By measuring the distance between these ripples at different periods in cosmic history, astronomers could determine whether the accelerating expansion of the universe has been constant or has changed over time.
This knowledge will be essential to understand the mysterious dark energy, which would represent 70% of the universe and would be the engine of its expansion.
You can share this story on social media: