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StarDateYour guide to the universe Author: Billy Henry
StarDate, the longest-running national radio science feature in the U.S., tells listeners what to look for in the night sky. Language: en-us Genres: Astronomy, Education, Science Contact email: Get it Feed URL: Get it iTunes ID: Get it |
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Going for a Ride
Thursday, 9 April, 2026
You might want to buckle up for this one. We’re going to take a wild ride through the universe. It’s a combination of several motions – involving our planet, our solar system, and our galaxy. First up is Earth’s motion around the Sun. Our planet’s average orbital speed is about 66,600 miles per hour. At that speed, it takes exactly one year for Earth to make one full turn. The Sun is moving as well, and it’s taking Earth and the rest of the solar system along for the ride. The Sun is about 27,000 light-years from the center of the Milky Way Galaxy. It circles around that center at almost 500,000 miles per hour. The galaxy is so huge, however, that it takes about 230 million years to complete one orbit. And that’s not the fastest motion we’re experiencing. The Milky Way belongs to a small cluster of galaxies, the Local Group. The group is being pulled toward the Virgo Cluster, which contains thousands of galaxies. And the Local Group, Virgo Cluster, and much more are being pulled in by the gravity of the Great Attractor – the center of an enormous collection of galaxies and dark matter. The Milky Way is speeding toward it at more than 1.3 million miles per hour. So while the ground beneath your feet feels steady, keep in mind that it’s on the move – tugged by the Sun, the galaxy, the Great Attractor – and perhaps even more. Script by Damond Benningfield
