A team of astronomers have developed a new method for measuring the Hubble Constant – the expansion rate of the universe. Using W. M. Keck Observatory’s adaptive optics (AO) system to observe three distant, gravitationally lensed quasars, they found that the universe is ballooning faster than previously measured. This first use of ground-based AO to obtain the Hubble Constant shows that ground-based measurements can provide a powerful alternative to Hubble Space Telescope (HST) data in the future. For now, these data combine with the HST to give a more precise result. The new measurement adds to the mystery over the crisis in cosmology; different methods keep giving different results, which adds to growing evidence that there is a problem with the standard cosmological model of the universe. Find out more in Keck Observatory’s news releases