Science is all about observing the world. But how do you study something you can’t see, smell, or hear — like the tiniest particles all around us? How do you test a new energy source when it doesn’t really exist yet?

These are the challenges that the world of physics often faces. You can come up with theories, using modeling and calculations, and devise some kind of experiment on paper to investigate things. But then you have to translate those ideas into tangible, real-world experiments, which is often incredibly challenging.

On today’s show, we peek behind the curtain of multimillion-dollar physics experiments that are changing the way we understand our world — and hear about some of the big challenges they face. We dig into the origins of the James Webb Space Telescope, talk with xkcd cartoonist Randall Munroe about some of his more outlandish — and complicated — physics calculations, and hear from accelerator physicist Suzie Sheehy about the physics experiments that changed the world.

Also heard on this week’s episode:

• When the first images from the James Webb Space Telescope were revealed just last year, they seemed to inspire a collective moment of awe. They offered stunning glimpses of deep space never before seen. We talk with astronomer and astrophysicist Garth Illingworth about the origin of the telescope, and what pushed him and his colleagues to design something they’d never even dared to imagine.
• Cartoonist Randall Munroe joins us to talk about his latest book “What If? 2,” in which he uses science to answer absurd questions from fans and readers.
• Suzie Sheehy is an experimental physicist, so she knows all about the challenges of creating places and spaces where she can test out her ideas. Her new book about famous experiments in physics is called “The Matter of Everything.”
• Dakotah Tyler wants to inspire the next generation of astrophysicists — and he’s taking to TikTok and Instagram to talk about space, stars, and dark matter in an approachable way.