Scientists have a new and more accurate measure of the expansion of the universe thanks to decades of data from the Hubble Space Telescope.
The new analysis of data from 32 years Hubble Space Telescope The observatory’s long research continues to understand how fast the universe is expanding and how fast that expansion is accelerating.
The number astronomers use to measure this is called the expansion. Hubble constant (Not for a telescope, but for astronomer Edwin Hubble who first measured it in 1929.) The Hubble constant is difficult to determine because different observatories look at different regions of user They gave different answers. But a new study expresses confidence that Hubble’s latest effort is accurate in terms of the expansion it sees, although it still differs from other observatories.
The new study confirms previous estimates of the rate of expansion based on Hubble observations, which show an expansion of about 45 miles (73 kilometers) per megaparsec. (The huge mongoose is The distance scale is equal to one million parsecs, or 3.26 million light years†
Related: The best Hubble Space Telescope pictures of all time!
“Given Hubble’s large sample size, there is only a one-in-a-million chance that astronomers are wrong due to unlucky clouds…a common barrier to seriously addressing a physics problem,” NASA said in a NASA report. Declaration Adam Rees, Nobel Prize winner and lead author of the study, paraphrased on Thursday (May 19).
Reese has affiliations with the Hubble Space Telescope Science Institute (STScI), as well as Johns Hopkins University in Baltimore, Maryland.
Reese and his collaborators won the Nobel Prize in 2011 after Hubble and other observatories confirmed that the universe… accelerates its expansion† Reiss calls Hubble’s recent effort a “magnum opus” because he draws on practically the entire history of the telescope, 32 years of space work, to provide an answer.
The Hubble data showed an expansion rate observed under a program called SHOES (Supernova, H0, for dark energy state comparison). NASA said the data set doubles up on a previous sample of measurements and also includes more than 1,000 Hubble orbits. The new measurement is also eight times more accurate than expectations for Hubble’s capabilities.
Attempts to measure how fast the universe is expanding usually focus on two distance markers. One of them is will benefit stars, variable stars that light up and dim at a constant rate; Its usefulness has been known since 1912, when astronomer Henrietta Swan-Levitt realized its importance in the images she was viewing.
Cepheids are good for plotting distances within the Milky Way (our galaxy) and in nearby galaxies. For greater distances, astronomers rely on them Type 1 supernova† These supernovae have a constant brightness (inherent brightness), allowing accurate estimates of their distances based on how bright they are in telescopes.
In the new study, NASA stated that “the team measured 42 supernova signs using Hubble. Since they were seen exploding at a rate of one per year, Hubble has, for all practical purposes, recorded as many supernovae as possible to explain the expansion of the universe.” (Again, Hubble has been in space for about 32 years, after it was launched on April 24, 1990; astronauts addressed a mirror defect that hampered early work in December 1993.)
But the extent of the expansion is still not fully aggregated across the various efforts. The new study says Hubble’s measurements are about 73 kilometers per megaparsec. But when observations of the deep universe are taken into account, the speed drops to about 62 miles (67.5 kilometers) per megaparsec.
The observations of the deep universe are mainly based on ESA measurements Planck’s missionwho noticed “echo” the big explosion that made up our universe. Echo is known as cosmic microwave background† NASA said astronomers were “confused” about why the two values differed, but suggested that we might need to rethink the underlying physics.
Reese said it’s best to view the rate of expansion not for its exact value for its time, but for its ramifications. “I don’t care about size, but I would love to use it to learn more about the universe,” Reese said in a NASA statement.
More measurements are expected in the next 20 years from James Webb Space TelescopeComplete a deep space work mission before looking at some of the first galaxies. NASA said Webb will look at CSN and Type 1a “at greater distances or at a much sharper resolution than Hubble can see.” This, in turn, could improve Hubble’s detection rate.
A paper based on the research will be published in the Astronomical Journal. a Pre-print version Available at arXiv.org.
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