There appears to be some unknown feature of the universe that is affecting its expansion, scientists have said.
New measurements from the Webb telescope – Nasa’s most powerful space observatory – could help explain one of the deepest mysteries of the cosmos, according to the researchers behind them.
For years, scientists have been troubled by an unusual feature of our universe. It appears to be expanding faster today than it did in the past – and researchers are not sure why.
Now the Webb telescope has confirmed those unexpected measurements, which were previously shown by Nasa’s Hubble Space Telescope. That suggests there is something unknown happening in the universe, rather than an error in that telescope’s measurements.
That might mean there are unknown forces at work in the universe, for instance, or that there is a gap in our understanding of the cosmos that could require new physics.
“The discrepancy between the observed expansion rate of the universe and the predictions of the standard model suggests that our understanding of the universe may be incomplete,” said Adam Riess, the lead author of a new paper on the findings. “With two Nasa flagship telescopes now confirming each other’s findings, we must take this [Hubble tension] problem very seriously—it’s a challenge but also an incredible opportunity to learn more about our universe.”
For decades, scientists have been trying to calculate what they call the “Hubble constant”, or the speed at which the universe is expanding. But recent research has given rise the “Hubble tension” or conflicts between the expected rate and the one that measurements show is happening.
The new research looked at the largest sample of Webb data, taken over its first two years, to verify that telescope’s measurement of the expansion. They used three different measurement techniques, looking at galaxies that have supernovae and using them to check how quickly they appeared to be moving.
They found that the new measurements were in line with those previous ones from the Hubble telescope. That rules out that the former telescope had made some inaccuracy – and indicate that it is in fact something to do with the universe.
Instead, researchers suggest there is something lacking in the current “standard model of cosmology”, our accepted framework of how the universe works.
A paper reporting the findings, ‘JWST Validates HST Distance Measurements: Selection of Supernova Subsample Explains Differences in JWST Estimates of Local H0’, is published in The Astrophysical Journal.
