The largest 3D map of the universe ever shows 47 million galaxies from the Milky Way to ‘cosmic noon’ — Space Photo of the Week

This snapshot is just one part of the most comprehensive and spectacular view of the universe ever. This is a web-like structure formed by millions of galaxies and dating back to ancient times.

Each tiny dot in the image represents a galaxy mapped by the Dark Energy Spectrometer (DESI). Galaxies are not randomly distributed. Instead, they form filaments or clusters known as the cosmic web. In between these clusters of bright galaxies are vast regions of sky known as voids, where few stars or galaxies exist.

This image is from the largest high-resolution 3D map of the universe ever created. DESI is mounted on the Nicholas U. Mayall 4-meter Telescope at Kitt Peak National Observatory in Arizona and uses 5,000 robotic fiber-optic sensors to capture light from distant celestial objects.

you may like

The five-year survey was expected to collect data on 34 million galaxies and quasars, the bright cores of young, distant galaxies. In fact, it detected more than 47 million, along with more than 20 million nearby stars in the Milky Way. The visualization published alongside the DESI map shows how DESI has grown over the past five years.

Some of the light captured in this image took billions of years to reach Kitt Peak, allowing scientists to go back in time and reconstruct how the universe evolved. The result is a three-dimensional view that shows not only where galaxies are located, but also how they have moved and clustered over time.

Beyond its visual impact, the image plays an important role in investigating mysterious dark energy, the name physicists have given to the force thought to be driving the accelerating expansion of the universe. It makes up about 70% of the universe, and its nature and distribution are one of the biggest questions in physics.

By comparing the distribution of galaxies at different times, researchers can track how dark energy has influenced the structure of the universe over the past 11 billion years. Early DESI data already suggests that dark energy may evolve throughout the history of the universe. This is a breakthrough that will fundamentally change scientists’ understanding of the universe and its ultimate fate.

This image is the result of extensive international cooperation. The project, led by Lawrence Berkeley National Laboratory and funded by the U.S. Department of Energy’s Office of Science, involved more than 900 researchers from more than 70 institutions.

DESI will continue observing the sky until 2028, expanding the map by about 20%. Future observations will target dimmer and more distant galaxies, as well as hard-to-see areas near the Milky Way (where stars get in the way) and the southern sky (where telescopes need to see more of Earth’s atmosphere). First results from the full dataset are expected in 2027.