The Hubble tension is a long-standing issue in cosmology, where different measurements of the universe’s expansion rate yield conflicting results. A new study using data from Type 1a supernovae in the Coma cluster has shed more light on this puzzle.
In 1929, Edwin Hubble discovered that galaxies farther away are moving away from us at a faster rate than closer ones, indicating an expanding universe. The Hubble-Lemaître Law describes the linear relationship between distance and velocity of galaxies. However, two measurements of the expansion rate – one from cosmic microwave background radiation and another from standard candles like supernovae – differ significantly.
The Coma cluster is used to estimate the Hubble constant, but previous attempts were limited by inaccurate distance measurements. The new study uses Type 1a supernovae to measure the distance with unprecedented precision. By analyzing data from multiple telescopes, researchers identified 12 high-quality supernovae in the Coma cluster.
Measuring the distance of the Coma cluster, the team found a value of 98.5 megaparsecs (Mpc). This corresponds to an Hubble constant of 76.5 km/s/Mpc – significantly different from the CMB measurement of 67.5 km/s/Mpc. The discrepancy raises questions about the accuracy of current measurements.
However, the study suggests that improved precision may not resolve the Hubble tension. Instead, it might reflect a fundamental difference between the two measurement methods. New data from upcoming missions like DESI and James Webb Space Telescope will provide crucial insights into this phenomenon. These instruments will observe 100,000 galaxies in the Coma cluster and other nearby clusters, increasing the precision of distance measurements.
The ongoing quest to resolve the Hubble tension highlights the importance of continued research and exploration in cosmology. As new data arrives, scientists will be better equipped to understand the nature of the universe’s expansion rate and its implications for our understanding of the cosmos.
Source: https://astrobites.org/2025/01/10/coma-hubble-tension