Latest Episodes

Moon and Regulus
February 23, 2024

The United States and China plan to build permanent bases on the Moon. For the people who inhabit those bases, daily life will be quite different from life on Earth. For starters, the Moon’s gravity i

February 22, 2024

By far the most numerous objects in the solar system are asteroids chunks of rock, metal, and ice. Scientists have discovered more than 1.3 million of them. They range from a few feet across to a fe

Vermin of the Skies
February 21, 2024

Attitudes can change. Thats as true in science as in anything else. Today, asteroids are considered some of the most interesting objects in the solar system. But that wasnt always the case. They wen

Moon and Pollux
February 20, 2024

Pollux, the brighter of the twin stars of Gemini, is a giant. Its expanded to about nine times the diameter of the Sun a beach ball to the Suns golf ball. Thats made Pollux much cooler than the

Venus and Mars
February 19, 2024

The planets that flank Earth huddle close together in the dawn sky over the next few days. Venus and Mars are quite low in the east-southeast during the waxing twilight, so you need a clear horizon to

Snake’s Head
February 18, 2024

Hydra, the water snake, is the largest of all the constellations and by far the longest. It spans more than 100 degrees almost a third of the way around the sky. So it takes a long time to climb i

Moon and Taurus
February 17, 2024

The Moon slides along one of the horns of Taurus tonight. At nightfall, the bulls bright eye, the star Aldebaran, is to the lower right of the Moon. And the tip of the horn, El Nath, is closer to the

Moon and Pleiades
February 16, 2024

The Suns birthplace has long since fallen apart. The Sun almost certainly was born in a cluster, with anywhere from dozens to thousands of siblings. Over a few hundred million years, though, the clus

Class G
February 15, 2024

The Sun is near the top of its class class G. Such stars all have about the same temperature, so they look yellow. Members of the class that are in the prime of life, as the Sun is, are also close

Moon and Jupiter
February 14, 2024

The average depth of the oceans on Earth is a little more than two miles. And the greatest depth is about seven miles. But thats little more than a big puddle compared to the ocean on Ganymede, the b