Swinburne-CSIRO Team Measures Hubble Constant From 1 Neutron Star Merger, Challenging New-Physics Fix
Updated
Updated · Universe Today · Jul 11
Swinburne-CSIRO Team Measures Hubble Constant From 1 Neutron Star Merger, Challenging New-Physics Fix
1 articles · Updated · Universe Today · Jul 11
Summary
A Swinburne- and CSIRO-led team derived a new Hubble constant from a neutron-star merger by combining gravitational-wave data with Hubble and global radio-telescope observations.
That late-Universe measurement landed closer to the early-Universe value from the cosmic microwave background than to supernova-based estimates, giving fresh weight to one side of the Hubble tension.
Nearly 1 year of follow-up tracked jets launched in the collision, whose months-long glow helped the researchers pin down the merger geometry needed for the expansion-rate calculation.
The result is still less precise than established methods, but the team says it is the strongest gravitational-wave evidence yet against proposals that both conflicting expansion rates can be reconciled by changing cosmology.
Published in The Astrophysical Journal, the study adds support for using more neutron-star mergers as an independent route to settle how fast the Universe is expanding.
Could ghostly echoes from dead stars prove our fundamental understanding of the universe is wrong?
If the universe expands slower than thought, what does this mean for the mysterious dark energy pulling it apart?
Resolving the Hubble Tension: Gravitational Wave Standard Sirens and the Universe’s Expansion Rate
Overview
In June 2026, researchers from Swinburne University of Technology and CSIRO announced a new measurement of the Universe's expansion rate by closely observing the aftermath of a neutron star merger. By combining data from gravitational wave detectors and traditional telescopes, they introduced a unique and independent method to determine how fast the Universe is expanding. This approach stands apart from the traditional cosmic distance ladder techniques and provides a fresh perspective for comparing results from both late and early Universe measurements. The new pathway is expected to help scientists better understand the Universe's fundamental properties and address long-standing questions about its expansion.