“An exciting possibility that we have misunderstood the universe.”

How fast is the universe expanding? This question is still intensely occupied by science. The rate of expansion is one critical factor. To determine them, astronomers must measure the distances of distant galaxies with high precision.

Nobel laureate identifies 'exciting possibility'

The Hubble Space Telescope, which has been measuring the expansion rate of the universe for 30 years, plays a key role in this. However, the results obtained differ from those obtained by the Planck Space Telescope of the European Space Agency (ESA).

Now NASA's Hubble and James Webb Space Telescopes are working together to produce the final measurements. According to one statement, this supports this NASA press release The assumption that something else – not measurement error – affects the rate of expansion.

If there were no measurement errors, there would still be “a real and exciting possibility that we have misunderstood the universe,” says Adam Ries, a physicist at Johns Hopkins University in Baltimore. Reiss won the Nobel Prize for discovering that the expansion of the universe is accelerating due to a mysterious phenomenon now called “dark energy.”

“Hubble effort” in focus

An initial observation by the James Webb Telescope in 2023 confirmed that Hubble's measurements of the expanding universe were correct. Now we want to look deeper into the universe and exclude data from distant stars. “We have now covered the full range of what Hubble observed, and we can rule out measurement error as a cause of the Hubble effort with a very high degree of certainty,” Reiss said.

The so-called “Hubble tension”, that is, the discrepancy between the measured values, is one of the great mysteries of cosmology. Pavel Krupa of the Helmholtz Institute for Radiation and Nuclear Physics at the University of Bonn explains it this way: “The universe appears to be expanding faster in our surroundings – a distance of about three billion light-years – than in its entirety. And this should not be the case.” The situation in reality.

NASA: Mystery remains

One from the James Webb Telescope Newly collected data It should now be linked to the Hubble data. “Combining Webb and Hubble gives us the best of both worlds,” Rees asserts.

But scientists still have some tasks ahead of them, especially regarding the Big Bang. “We have to figure out if we're missing something and how we can connect the beginning of the universe to the present,” says Rees. Mystery remains, NASA summarized the current state of the science.