The Hubble Space Telescope has reached a new milestone in its work to find out how fast the universe is expanding, and it supports the idea that something strange is happening in our universe, NASA says.
In recent years, astronomers have used telescopes like Hubble to understand exactly how fast our universe is expanding.
But as those measurements have become more precise, they have also shown something strange. There is a key difference between the rate of expansion of the universe around us, compared to observations from just after the Big Bang.
Scientists cannot explain that discrepancy. But it does suggest that “something strange” is happening in our universe, which could be the result of unknown new physics, NASA says.
For the past 30 years, Hubble has been collecting information on a set of “milestone markers” in space and time that can be used to track the rate of expansion of the universe as they recede from us.
It has now calibrated more than 40 of the markers, NASA announced, allowing for even greater precision than before.
“You are getting the most accurate measurement of the expansion rate of the universe from the standard of telescopes and cosmic landmark markers,” said Nobel laureate Adam Riess of the Space Telescope Science Institute (STScI) and Johns Hopkins University. in Baltimore, Maryland, in a statement.
He is the leader of a team of scientists that has published a new paper detailing the Hubble Space Telescope’s most important and probably last such upgrade, which duplicated the previous set of milestone markers and reanalyzed existing data.
The search for an accurate measurement of how fast space was expanding came about when the American astronomer Edwin Hubble said that galaxies outside of our own seemed to be moving away from us, and getting faster the farther away they were from us. Scientists have been seeking a better understanding of that expansion ever since.
(Both the rate of expansion and the space telescope that has been investigating it are called Hubble, in honor of the astronomer’s work.)
However, when the space telescope began to collect information on the expansion of the universe, it turned out to be faster than the models had predicted. Astronomers predict that it should be about 67.5 kilometers per second per megaparsec, with an error range of ±0.5, but observations show it to be around 73.
There is only one chance in a million that astronomers have been wrong. Instead, this suggests that the evolution and expansion of the universe is more complicated than we thought, and that there is more to learn about how the universe is changing.
Scientists hope to delve into that difficulty with the new James Webb Space Telescope, which recently launched into space and will soon send back its first observations. That should allow them to see new milestones that are even further away and in better resolution.