How Big is the Universe?

A special “tickle attack” Mailbag edition of Tumble! We’re tackling your questions about whether animals can be tickled, and why we laugh when we’re tickled. David Leavens, a professor of psychology, helps us break down the not-so-silly science of tickling. Plus, a brand NEW SONG ...  Show more

Do trees think? That’s what our listener Alden wants to know. He has an idea that scientists might study mushroom roots to find out if trees are sending messages. Is that true? And if so, what do trees have to say?!We travel deep into the forest with a young soil scientist named ...  Show more

Those tiny pinpoints of light glittering in the night sky are actually incredibly distant, giant, churning balls of gas. They produce huge quantities of light and heat. In this episode, Mars interviews the biggest star in his eyes: the sun! We also ask astronomer Moiya McTier to ...  Show more

In the early 1900s, Henrietta Leavitt made one of the most important discoveries in the history of astronomy: a yardstick to measure distances to faraway stars. Using this tool, scientists eventually transformed our understanding of the universe. They realized space was expanding ...  Show more

How to Measure the UniverseBrian Cox and Robin Ince are joined on stage by comedian Jo Brand, and physicists Prof Jo Dunkley and Dr Adam Masters to look at how we go about measuring our universe, from measuring the contents of atmospheres of planets and moons at the outer edges o ...  Show more

In the early 1900s, Henrietta Leavitt made one of the most important discoveries in the history of astronomy: a yardstick to measure distances to faraway stars. Using this tool, scientists eventually transformed our understanding of the universe. They realized space was expanding ...  Show more