Hubble Science: Expansion Rate: The Hubble Tension

  • Released Tuesday, September 12, 2023

When the Hubble Space Telescope launched, one of its main goals was to measure the rate at which our universe is expanding.

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.

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.

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Credit: NASA's Goddard Space Flight Center

Producer & Director: James Leigh

Editor: Lucy Lund

Director of Photography: James Ball

Additional Editing & Photography: Matthew Duncan

Executive Producers: James Leigh & Matthew Duncan

Production & Post: Origin Films

Video Credit:
Hubble Space Telescope Animation
Credit: M. Kornmesser (ESA/Hubble)

Dark Energy Expansion Graph
Credit: NASA's Goddard Space Flight Center

Dark Energy Expansion Animation
Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

Hubble Extreme Deep Field Fly Through
Credit: NASA, ESA, and F. Summers, L. Frattare, T. Davis, Z. Levay, and G. Bacon (Viz3D Team, STScI)

James Webb Space Telescope Animations
Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

Music Credit:
“Alpha and Omega” by Laurent Parisi [SACEM] via KTSA Publishing [SACEM] and Universal Production Music

“Cosmic Call” by Immersive Music (Via Shutterstock Music)

Vertical Version

This vertical version of the episode is for IGTV or Snapchat. The IGTV episode can be pulled into Instagram Stories and the regular Instagram feed.


Please give credit for this item to:
NASA's Goddard Space Flight Center. However, please credit individual items as indicated above.

Release date

This page was originally published on Tuesday, September 12, 2023.
This page was last updated on Thursday, June 8, 2023 at 2:31 PM EDT.


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