To calculate much greater distances, astronomers use exploding stars called Type Ia supernovae.Ĭombined, these objects built a "cosmic distance ladder" across the universe and are essential to measuring the expansion rate of the universe, called the Hubble constant after Edwin Hubble. Cepheids have long been the gold standard of cosmic mile markers since their utility was discovered by astronomer Henrietta Swan Leavitt in 1912. When NASA conceived of a large space telescope in the 1970s, one of the primary justifications for the expense and extraordinary technical effort was to be able to resolve Cepheids, stars that brighten and dim periodically, seen inside our Milky Way and external galaxies. His team also reanalyzed all of the prior data, with the whole dataset now including over 1,000 Hubble orbits.
The new results more than double the prior sample of cosmic distance markers.
#MILKY CHANCE LYRICS UPDATE#
Riess's team's paper, to be published in the Special Focus issue of The Astrophysical Journal reports on completing the biggest and likely last major update on the Hubble constant.
This is likely Hubble's magnum opus, because it would take another 30 years of Hubble's life to even double this sample size," Riess said. "This is what the Hubble Space Telescope was built to do, using the best techniques we know to do it. Riess leads a scientific collaboration investigating the universe's expansion rate called SH0ES, which stands for Supernova, H0, for the Equation of State of Dark Energy. "You are getting the most precise measure of the expansion rate for the universe from the gold standard of telescopes and cosmic mile markers," said Nobel Laureate Adam Riess of the Space Telescope Science Institute (STScI) and the Johns Hopkins University in Baltimore, Maryland. But Hubble data, encompassing a variety of cosmic objects that serve as distance markers, support the idea that something weird is going on, possibly involving brand new physics. The cause of this discrepancy remains a mystery. In recent years, thanks to data from Hubble and other telescopes, astronomers found another twist: a discrepancy between the expansion rate as measured in the local universe compared to independent observations from right after the big bang, which predict a different expansion value. In 1998, this led to the discovery of "dark energy," a mysterious repulsive force accelerating the universe's expansion. 'Pursuit of the universe's expansion rate began in the 1920s with measurements by astronomers Edwin P.
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