Three decades of space telescope observations converge on a precise value for the Hubble constant - Phys.org

Completing a nearly 30-year marathon, NASA's Hubble Space Telescope has calibrated more than 40 "milepost markers" of space and time to help scientists precisely measure the expansion rate of the universe—a quest with a plot twist.

This collection of 36 images from NASA's Hubble Space Telescope features galaxies that are all hosts to both Cepheid variables and supernovae. These two celestial phenomena are both crucial tools use… [+7937 chars]

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