The Astrophysics Podcast

How do we know how old a star is? Unlike trees, stars don't have rings we can count, and determining their ages requires us to understand the complicated physics happening deep inside them. Stellar models are essential to this process, but even our best models have significant uncertainties in how they treat processes like convection and mixing. Dr. Meridith Joyce is a computational astrophysicist who works on improving these models, in order to better understand stars. In this episode, we talk about how we determine the ages of stars, what their oscillations can tell us about their interiors, and take a closer look at one particularly famous star: Betelgeuse.

Shockwaves are a familiar phenomenon here on Earth. In astrophysics, they play a role in some of the most powerful events in the universe, from exploding stars to gamma ray bursts. Shockwaves can transform enormous amounts of energy and carry information about events that are otherwise impossible to observe directly. Dr. Chris Irwin studies how these shocks form and evolve, and how we can use them to learn about cosmic explosions.

The Theory of Relativity was discovered by Einstein over a century ago, and it tells us how time and space are distorted when moving close to the speed of light. We mere earthlings don't get the opportunity to move that fast, but there are some phenomena in astrophysics that move very fast; more than 99.9999% of the speed of light. Ranadeep Dastidar is a computational modeler who writes code to predict and interpret these "relativistic" phenomena.

Abigail Polin is back, and we are doing another astrophysics Q&A! This time, our questions come from a class of third graders in Indiana. You'll be surprised at how some of the simplest questions can lead us down a very complex path!

This episode we get back to the objects that inspired the whole field of astrophysics -- stars. Those little points of light that first inspired us as children are incredible physics laboratories that we can still use today to learn about plasma physics, turbulence, and nuclear reactions. Dr. Jeff Gerber tells us why he made his career out of studying how stars work, and how much we still have to learn about these giant balls of plasma.