All things in the cosmos have a lifespan, from the smallest particles to the most ancient suns. Everything has its season. Every season must come to an end.

And this episode marks the end of Orbital Path.

So, for the last transit of our podcast, Dr. Michelle Thaller and producer David Schulman join NASA astrobiologist Dr. Jen Eigenbrode on a site visit to one of Michelle’s very favorite places at Goddard Space Flight Center. It’s building 29, where NASA builds and tests spacecraft in some of the most extreme conditions found anywhere on earth. 

Orbital Path is produced by David Schulman. 




Our editor is Andrea Mustain. Production oversight by John Barth and Genevieve Sponsler. Hosted by Michelle Thaller.




Support for Orbital Path is provided by the Alfred P. Sloan Foundation, enhancing public understanding of science, technology, and economic performance.

Image credit: NASA

Asteroids, as the dinosaurs found out, can have big effects on life on Earth. 

Sixty-five million years ago, an asteroid crashed into the Yucatán. The impact caused apocalyptic tsunamis and volcanic eruptions. Grit and ash blotted out the sun. It wiped out species that had roamed the Earth for millions of years.

Yet asteroid hits also were critical to the origins of life on Earth. Asteroids may well have been the bringers of water, of carbon, even of amino acids — the building blocks of life.

That’s a big reason why NASA is on a mission to Bennu. This asteroid is like an ancient fossil of our solar system — largely unchanged since the time the planets formed.

In December, after a billion-mile journey, NASA’s Osiris-Rex mission arrives at Bennu. And, for the first time, a spacecraft will try to actually bring back an asteroid sample to Earth.

On this episode of Orbital Path, Dr. Michelle Thaller sits down with Dr. Amy Simon — a senior scientist at NASA’s Goddard Space Flight Center, and a key player on the Osiris-Rex mission. Michelle and Amy talk about the mission, Amy’s work to probe the origins of the solar system, and one other thing: 

The remote chance that Bennu, someday, could collide with Earth.

Orbital Path is produced by David Schulman. 

Our editor is Andrea Mustain. Production oversight by John Barth and Genevieve Sponsler.

Support for Orbital Path is provided by the Alfred P. Sloan Foundation, enhancing public understanding of science, technology, and economic performance.

Image credit: NASA/Goddard/University of Arizona.

To make a black hole, you need to think big. Really big.

Start with a star much bigger than the sun — the bigger the better. Then settle in, and wait a few million years for your star to die.

That should do the trick, if you want to get yourself a garden-variety black hole. But there’s another kind of black hole. They are mind-boggling in size. And deeply mysterious:

Super-massive black holes.

Last year, in the journal Nature, a team of astronomers reported finding one with the mass of 800 million suns. It’s the most distant black hole in the known universe. And it’s so ancient, it dates to a time when it seems light itself was only just beginning to move.

On this episode of Orbital Path, Dr. Michelle Thaller talks with astrophysicist Chiara Mingarelli — Flatiron Research Fellow at the Center for Computational Astrophysics in New York. Using a special gravitational wave observatory, Dr. Mingarelli is part of a cadre of astronomers hoping ancient super-massive black holes will soon reveal mysteries dating to the dawn of our universe.

Orbital Path is produced by David Schulman.

Our editor is Andrea Mustain. Production oversight by John Barth and Genevieve Sponsler.

Support for Orbital Path is provided by the Alfred P. Sloan Foundation, enhancing public understanding of science, technology, and economic performance.

Image credit: NASA artist’s rendering of a super-massive black hole.