NASA's Curious Universe

The James Webb Space Telescope is doing something astronomers dreamed about for decades: peering into our universe’s early past, a period known as cosmic dawn. A new NASA documentary—also called Cosmic Dawn—chronicles the inside story of Webb’s design, construction, and launch. John Mather, who won the 2006 Nobel Prize for Physics, proposed the telescope and led its science team for decades. In this interview, Mather talks about his life, his research, and the pre-dawn phone call telling him he had won the Nobel Prize.

Find more at nasa.gov/cosmicdawn

This episode was updated on Dec. 19, 2025, to provide a video version on platforms that support video.

Have you ever dreamed of spending a day in space? Humans have lived aboard the International Space Station for 25 years—or more than 9,000 consecutive days. In this episode originally published in 2021, experience a day in the life of astronauts Shane Kimbrough, Megan McArthur, and Thomas Pesquet living and working on the International Space Station. 

In the space between stars, dark clouds of gas, dust, and ice mingle in a chemical laboratory unlike any on Earth. Ewine van Dishoeck, an astronomer who studies molecules in space and who helped develop an instrument aboard NASA’s James Webb Space Telescope, explains how Webb is revealing new details about the formation of stars and planets. This research could help unlock a key question about Earth: how did our planet end up with water and the ingredients for life? 

NASA’s James Webb Space Telescope is hard at work answering our biggest questions about the birth of our universe and faraway galaxies. But some astronomers are pointing its powerful eyes much closer to home. In this episode, Caltech astronomer Katherine de Kleer explains how Webb is rewriting our understanding of objects within our solar system–from space rocks in the asteroid belt to the icy and volcanic moons of Jupiter and Saturn.

Some exoplanets—like a gas giant with rain made of glass and 5,000-mile-per-hour winds—sound like worlds dreamed up by a science fiction writer. But they’re real. From light-years away, scientists can uncover details about planets orbiting distant stars and even ask whether some exoplanets could support life. Néstor Espinoza, an astronomer at the Space Telescope Science Institute, explains how NASA’s James Webb Space Telescope is revealing new details about exoplanets, especially rocky worlds like Earth.

With the James Webb Space Telescope, we are seeing the early universe like never before. Webb produces beautiful images and detailed scientific data that leave astronomers in awe. In this episode, Mic Bagley, a NASA scientist on the Webb team, guides us through new discoveries made possible by Webb. Mic tells the story of a remarkable galaxy discovered in the early days of Webb’s science mission and explains why Webb is teaching us “everything” about how galaxies form and evolve. 

In space, microgravity changes the body. Body fluids shift from the legs toward the head, the back of our eyes flatten, we lose muscle strength, our bones lose some of their density, and even the amount of blood pumped by the heart with each beat drops. To learn more about how microgravity affects the human body and develop new ways to help astronauts stay healthy, scientists are asking dozens of volunteers to spend 60 days in bed with their heads tilted down at a specific angle. This research approach tricks the body into reacting very similarly to how it would if a person was aboard the International Space Station for a longer-term mission. Join Andreas Joshi, a volunteer who agreed to be part of this bedrest work, and two NASA scientists leading the study. They’re investigating different ways to combat space-based muscle loss and improve astronauts’ sense of balance by, among other things, teaching volunteers like Joshi to play video games with their feet.  

NASA has a record of Earth observations going back more than 50 years. What might be in store for the next 50 years? In this finale of our Earth series, we hear from two scientists helping to chart the course of NASA Earth science. There are still many unanswered questions about our home planet. As the only planet that we know to have life, studying Earth is also crucial as NASA searches for other habitable worlds.

Take a deep breath, and you’re inhaling oxygen from Earth’s atmosphere. Take a walk outside, and the atmosphere is shielding you from harmful radiation. NASA research provides crucial data to understand air quality and the intricate processes happening in the sky above us. In this episode, hear the inside story of NASA’s research into the ozone layer. Left unchecked, our reliance on ozone-depleting chemicals threatened to expose the entire planet to dangerous UV radiation. We’ll also fly along with Laura Judd, a NASA scientist studying air quality in the U.S. and around the world.

Earth has an incredibly varied and ever-changing landscape—jagged mountains, arid deserts, lush rainforests, rolling wheat fields. Before NASA came on the scene, no one was keeping a systematic eye on the ground from above. NASA scientist Brad Doorn explains how one long-running satellite program collects the data farmers need to grow the crops that feed the world.