At a Glance
- The universe’s expansion rate, known as the Hubble constant, is measured to be faster than predictions, highlighting a growing discrepancy called the Hubble tension.
- Two methods—observations of distant galaxies and measurements within the local universe—yield conflicting Hubble constant values, challenging existing cosmological models.
- Using Type Ia supernovae in the Coma Cluster, researchers calculated the Hubble constant at 76.5 km/s/Mpc, emphasizing the conflict with early-universe predictions.
- The persistent tension suggests potential flaws or missing components in long-standing models of the universe’s expansion and behavior.
- Scientists aim to resolve the Hubble tension through further studies, which could lead to groundbreaking revisions in our understanding of cosmology.
A new study has confirmed what many researchers have long suspected: the universe is expanding much faster than our current understanding of physics can explain. This discrepancy between predictions and actual measurements, known as the Hubble tension, is getting stronger with every new result. The latest findings, published in The Astrophysical Journal Letters, show that the rate of expansion, or the Hubble constant, is higher than expected, posing a significant challenge to cosmological models.
The Hubble constant refers to the rate at which the universe is expanding. Scientists have been working for decades to measure this value, which tells us how quickly galaxies are moving apart. The problem is that two different methods of measuring this rate—one based on observations of distant galaxies and one based on measurements within our local universe—are giving different results. This has led to the Hubble tension, a disagreement between theory and observation that scientists are still trying to resolve.
In the new study, researchers used a more precise technique to measure the Hubble constant by studying the Coma Cluster, a group of galaxies relatively close to Earth. By observing Type Ia supernovae in this cluster, they were able to more accurately measure its distance, which helped improve the calculation of the Hubble constant. The result reached 76.5 kilometers per second per megaparsec, meaning the universe expands at this speed for every 3.26 million light-years. However, this value still conflicts with predictions from the early universe, suggesting a flaw in our current cosmological models.
The findings are significant because they provide strong evidence that the Hubble tension is accurate and may be pointing to issues with our understanding of the universe’s behavior. The discrepancy could mean that our models, which have been used for decades, are missing something important. “We’re at a point where we’re pressing […] hard against the models we’ve been using for two and a half decades, and we’re seeing that things aren’t matching up,” said Dan Scolnic, the study’s lead author. Scientists hope that further research will help solve this puzzle, possibly reshaping our view of the cosmos.
References
- Chelini, M. C. & Duke University. (2025, January 17). Turning the Hubble tension into a crisis: New measurement confirms universe is expanding too fast for current models. Phys.Org; Duke University. https://phys.org/news/2025-01-hubble-tension-crisis-universe-fast.html
- Scolnic, D., Riess, A. G., Murakami, Y. S., Peterson, E. R., Brout, D., Acevedo, M., Carreres, B., Jones, D. O., Said, K., Howlett, C., & Anand, G. S. (2025). The hubble tension in our own backyard: Desi and the nearness of the coma cluster. The Astrophysical Journal Letters, 979(1), L9. https://doi.org/10.3847/2041-8213/ada0bd
