StarDate debuted in 1978, making it the longest-running national radio science feature in the country. It airs on more than 300 radio stations. It has been hosted by Billy Henry since July 2019.
StarDate tells listeners what to look for in the night sky, and explains the science, history, and skylore behind these objects. It also keeps listeners up to date on the latest research findings and space missions. And it offers tidbits on astronomy in the arts and popular culture, providing ways for people with diverse interests to keep up with the universe.
StarDate is a production of The University of Texas McDonald Observatory, which also produces the bi-monthly StarDate magazine.
The Voice of StarDate
Billy Henry, a voice talent, musician, composer, and college lecturer in Austin is the third narrator of the StarDate radio program. Read more »
The Music of StarDate
The StarDate background music was written by Bill Harwell and Patterson Barrett specifically for StarDate.
More Than 40 Years and Counting!
StarDate is radio’s longest-running nationally aired science program. It began in 1977 as a daily telephone message service by McDonald Observatory. It was picked up by Austin radio station KLBJ-FM, and aired as “Have You Seen the Stars Tonight?” beginning in June 1977. With a grant from the National Science Foundation, the program became “Star Date,” and began airing nationally, seven days per week, on October 1, 1978. It quickly reached more than 1,000 stations across the country. Read more »
Today’s Episode
Moon and Saturn
The solar system is pretty settled. The planets appear to be following orbits that have remained stable for billions of years. But in the early days, things might have been a lot more chaotic. According to one model, in fact, the giant planets Jupiter and Saturn might have moved much closer to the Sun before they moved back out again.
The planets probably took shape from a disk of gas and dust around the Sun. Small bits of material stuck together to make bigger bits, all the way up to planets. But much of the material remained free. There was enough of it to exert both a drag and a pull on the giant planets.
In this model, Jupiter — the Sun’s heaviest planet — was born at about two-thirds of its present distance from the Sun. It quickly moved inward, though, all the way to the orbit of Mars. Saturn — the second-most-massive planet — was dragged inward as well. Jupiter and Saturn thinned out the supply of gas and dust and the leftover planetary building blocks — either by scooping them up or kicking them away from the Sun. That changed the gravitational balance of the solar system. Jupiter and Saturn moved outward — settling into their current stable orbits around the Sun.
Saturn is in the dawn sky now, and looks like a bright golden star. Unlike a star, though, it doesn’t twinkle — its light holds steady. Tomorrow, it will stand close to the left of the Moon. The Moon will pass between Saturn and Mars the next morning; more about that tomorrow.
Script by Damond Benningfield
Upcoming Topics
May 6-12: “The Butting Ones”
One of the horns of the bull is marked by the star “Elnath” — a name that means “the butting one.” The name has a special significance for Star Date and its fans, and we’ll explain why.
April 29-May 5: Planet Parade
The Moon will pass by a parade of planets in the dawn sky late this week, and we’ll have details. We’ll also talk about a protective “blanket” around Earth, a small discovery, and more.
April 22-28: Taking a Trip
A trip around the world would take a while, even in a passenger jet. But it’s the blink of an eye compared to the time it would take to go around a supergiant star.