Chile's ACT telescope adds fuel to the 'Hubble tension' mystery
The Atacama Cosmology Telescope (ACT) in Chile just dropped its final results, and things are getting even trickier for scientists.
The big issue? Two different methods for measuring how fast our universe is expanding—one looking at nearby exploding stars, the other at ancient cosmic "fossil light"—still don't agree.
ACT's new data confirms this stubborn mismatch, keeping one of astronomy's biggest debates wide open.
Why this matters for our understanding of space
ACT's super-detailed maps of the Cosmic Microwave Background (the universe's oldest light) give us a sharper look than ever before, building on what we learned from Europe's Planck mission.
These results help rule out some outdated theories about how the universe grows and narrow down which models actually fit.
For anyone curious about how space works, it means there are still plenty of cosmic puzzles left to solve!