When the Hubble Space Telescope launched, one of its main goals was to measure the rate at which our universe is expanding. br br That rate is called the “Hubble Constant” – named after the astronomer Edwin Hubble, who contributed to the discovery of the universe’s expansion. However, the expected value of the expansion rate is different depending on what equipment is being used to determine it.br br In this video, Nobel Laureate Dr. Adam Riess explains this phenomenon known as “Hubble Tension,” and how important this mystery is to our understanding of the universe.br br For more information, visit . br br Credit: NASA's Goddard Space Flight Center br br Producer & Director: James Leighbr br Editor: Lucy Lundbr br Director of Photography: James Ballbr br Additional Editing & Photography: Matthew Duncanbr br Executive Producers: James Leigh & Matthew Duncanbr br Production & Post: Origin Films br br Video Credit:br Hubble Space Telescope Animationbr Credit: M. Kornmesser (ESAHubble)br br Dark Energy Expansion Graphbr Credit: NASA's Goddard Space Flight Centerbr br Dark Energy Expansion Animation br Credit: NASA's Goddard Space Flight Center Conceptual Image Labbr br Hubble Extreme Deep Field Fly Throughbr Credit: NASA, ESA, and F. Summers, L. Frattare, T. Davis, Z. Levay, and G.