New observations from the NASA/ESA/CSA James Webb Space Telescope confirms previous measurements by the NASA/ESA Hubble Space Telescope of distances between nearby stars and galaxies, offering a crucial cross-check to address the mismatch in measurements of the Universe’s mysterious expansion. Known as the Hubble tension, the discrepancy remains unexplained even by the best cosmology models.
“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 Nobel laureate and Johns Hopkins University’s Professor Adam Riess.
“With two NASA flagship telescopes now confirming each other’s findings, we must take this problem very seriously — it’s a challenge but also an incredible opportunity to learn more about our Universe.”
The new research builds on Professor Riess’ Nobel Prize-winning discovery that the Universe’s expansion is accelerating owing to a mysterious dark energy permeating vast stretches of space between stars and galaxies.
The authors used the largest sample of Webb data collected over its first two years in space to verify the Hubble telescope’s measure of the expansion rate of the Universe, a number known as the Hubble constant.
They used three different methods to measure distances to galaxies that hosted supernovae, focusing on distances previously gauged by the Hubble telescope and known to produce the most precise ‘local’ measurements of this number.
Observations from both telescopes aligned closely, revealing that Hubble’s measurements are accurate and ruling out an inaccuracy large enough to attribute the tension to an error by Hubble.
Still, the Hubble constant remains a puzzle because measurements based on telescope observations of the present Universe produce higher values compared to projections made using the Standard Model of cosmology, a widely accepted framework of how the Universe…
Read the full article here
