The night sky has just gotten a lot sharper. Scientists have finished creating the most detailed radio map of the universe ever made — and it's bigger, clearer, and more powerful than anything that came before it.
The project is called the Very Large Array Sky Survey, or VLASS. For nearly nine years, from September 2017 through February 2026, a telescope in the New Mexico desert scanned the heavens day and night. That telescope is the U.S. National Science Foundation's Very Large Array, a cluster of 28 massive radio antennas spread across the desert floor. Altogether, the survey logged roughly 6,500 hours of observation time.
The numbers behind VLASS are staggering. It mapped about 34,000 square degrees of sky — covering nearly the entire portion of the heavens visible from the Northern Hemisphere. It produced roughly half a petabyte of raw data, and scientists expect the final processed version to reach about 2 petabytes. That's more data than millions of high-definition movies combined. The survey also captured the sky three and a half times over, giving scientists a way to spot things that change or flash suddenly across the cosmos.
What makes VLASS special isn't just size — it's precision. The survey achieved an angular resolution of about 2.5 arcseconds, making it the sharpest full-sky radio map ever created. That's like being able to spot a basketball from 180 miles away. Amy Kimball, who heads VLASS operations, said the achievement finally closes a gap between radio astronomy and other kinds of sky-watching.
"With VLASS, we now have a radio map of the sky that matches the resolution of modern optical and infrared surveys," Kimball said. "This opens the door to truly multiwavelength discoveries at a level of detail that was not previously possible."
Radio waves are invisible to human eyes, but they reveal things optical light cannot. VLASS can peer through clouds of cosmic dust, detect hidden explosions, and trace the behavior of magnetic fields that stretch across galaxies. The survey observed at frequencies between 2 and 4 gigahertz, and it captured data on the polarization, or orientation, of radio waves — information that helps scientists understand magnetism throughout the universe.
Scientists will use the data to hunt for short-lived events like supernova explosions and gamma-ray bursts, map how galaxies have changed over billions of years, and uncover structures in our own Milky Way that have never been seen before.
Mark Lacy, VLASS project director, called the survey a long-term investment rather than a one-time project.
"VLASS is not just a survey; it is a long-term investment in the future of astrophysics," Lacy said. "Its combination of depth, coverage and accessibility ensures that it will remain a foundational resource for the community."
The data is being released publicly, freely available to scientists and curious minds everywhere. As processing continues over the coming years, more discoveries are expected to emerge from this enormous atlas of the radio sky.