Something is messing with our universe, and that something is the enduring mystery astronomers have dubbed dark energy –which comprises about two-thirds of the mass and energy in the universe. Determining how rapidly the universe is expanding is key to understanding our cosmic fate, but with more precise data has come a conundrum, reports the University of California Berkeley: “estimates based on measurements within our local universe don’t agree with extrapolations from the era shortly after the Big Bang 13.8 billion years ago. A new estimate of the local expansion rate — the Hubble constant, or H0 (H-naught) — reinforces that discrepancy.”