StarDate, the longest-running national radio science feature in the U.S., tells listeners what to look for in the night sky.
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McDonald Observatory Podcasts
Venus doesn’t have any moons. But it does share its orbit around the Sun. Astronomers have discovered 20 asteroids known as “co-orbitals,” but there could be many more. These big space rocks follow roughly the same path as Venus. But they won’t stay in that lane forever. And when they leave it, they could threaten Earth. These objects are nudged al…
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California is the land of the stars. It’s also in the stars as the California Nebula – a cloud of gas and dust that looks like the outline of the state. It’s more than a thousand light-years away, in Perseus. The nebula belongs to a giant star-forming complex – the Perseus O-B-2 association. The region has given birth to many class O and B stars – …
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Xi Persei doesn’t look all that imposing. The star shines at fourth magnitude, so it’s visible under dark skies, but not from cities and towns. But that’s only because it’s a long way off – about 1200 light-years. In reality, it’s one of the most impressive stars visible to the human eye. Perseus climbs the eastern sky on autumn evenings. It consis…
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For decades, Regulus had astronomers fooled. The star is bright, hot, and blue – an indication that it was quite young. Most estimates put its age at no more than a hundred million years – about two percent the age of the Sun. Instead, it’s at least a billion years old. But like a vampire, it’s been rejuvenated by taking the life’s blood of a compa…
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The Milky Way is a giant among galaxies – a hundred thousand light-years in diameter. But a few galaxies make the Milky Way look like a mere bauble by comparison. They span millions of light-years – puffed up by the action of supermassive black holes. These monsters are known as giant radio galaxies. Not only are they large, but they produce enormo…
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Deneb, the brightest star of Cygnus, stands high overhead as night falls at this time of year. And it really is a brilliant star – tens of thousands of times brighter than the Sun. But if we could tune our eyes to see radio waves, Deneb wouldn’t even register. Instead, the swan’s leading light would be Cygnus A – one of the brightest radio galaxies…
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Floating through the clouds at Jupiter’s equator sounds like a celestial carnival ride. The equator spins at about 28,000 miles per hour – 28 times faster than Earth’s equator. So the Sun, moons, and stars would zip across the sky in a hurry. Jupiter is the largest planet in the solar system – 11 times Earth’s diameter. It also spins faster than an…
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If you’d like to thank your lucky stars for a bit of good fortune, we have two stars for you to look at. They’re the brightest stars of Aquarius. Both of them have names that mean “lucky.” The brighter of the two is Sadalsuud. The name comes from an Arabic phrase that means something along the lines of “luckiest of the lucky.” When the name was bes…
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Stars like the Sun go through several distinct phases of life, from embryo to corpse. Consider Aldebaran, the bright eye of Taurus, which accompanies the Moon tonight. It’s more than six billion years old – older than the Sun. And it’s well into “old age.” Aldebaran was born when a cloud of gas and dust collapsed. For millions of years, it shined a…
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The Moon barrels through the Pleiades star cluster this evening. It’ll pass directly in front of the cluster, briefly blocking most of its stars from view. The Pleiades is the most famous of all star clusters. It’s also known as the Seven Sisters, but under dark skies – with no Moon in the way – you might actually see nine stars or more. But that’s…
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