What is the Hubble Tension?

There's a crisis in cosmology when it comes to understanding a little thing like the acceleration of our universe, aka The Hubble Tension. And in this episode, Izzie Clarke and Dr Becky Smethurst are digging into what this is and (trying to) explain the science behind it. A huge thank you to our guests, (Nobel Prize winning-) Professor Adam Riess from John Hopkins University and Professor Silvia Galli from Institut d'Astrophysique de Paris. Join The Supermassive Club for ad-free listening, forum access, and extra content from the team. And email your questions to podcast@ras.ac.uk or

You can listen to What is the Hubble Tension? online on Radio and Podcast. Open the player on this page to stream the available audio.

What is the Hubble Tension? is an episode from The Supermassive Podcast by Izzie Clarke.

This episode is 1:05:11 long.

This episode was published on Feb 26, 2026.

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