After 2 years in space, the James Webb telescope has broken cosmology. Can it be fixed? (Ben Turner, 12/22/23, Live Science)

But over the past decade, an alarming hole has been growing in this picture: Depending on where astronomers look, the rate of the universe’s expansion (a value called the Hubble constant) varies significantly.

Now, on the second anniversary of its launch, the James Webb Space Telescope (JWST) has cemented the discrepancy with stunningly precise new observations that threaten to upend the standard model of cosmology.

The new physics needed to modify or even replace the 40-year-old theory is now a topic of fierce debate.

“It’s a disagreement that has to make us wonder if we really do understand the composition of the universe and the physics of the universe,” Adam Riess, a professor of astronomy at Johns Hopkins University who led the team that made the new JWST measurements, told Live Science.

Relax, son, no one thought we understood.