Welcome to StarDate
Home of America’s longest-running national daily astronomy radio feature.
And so much more.
Stardate:
January 21, 2026Radio: Today’s Episode
Premium Same-Day Audio Access lets you stream episodes of StarDate the same day they air.
Log in or subscribe now to listen!
Radio: Yesterday’s Episode
Lambda Orionis
A monster in a land of monsters
/RSS Feed
Stargazing
Osiris
In ancient Greece and Rome, Orion was known as a mighty hunter. But in ancient Egypt, the figure was even mightier. It represented Osiris, the god of the underworld. In fact, Osiris was thought to reside in the stars of Orion’s Belt.
Lambda Orionis
Orion is in the east and southeast at nightfall. Bright orange Betelgeuse marks its left shoulder. Lambda Orionis, to the upper right of Betelgeuse, looks fainter, but it consists of two monster stars, one of which may be 200,000 times brighter than the Sun.
Doomed Companion?
Betelgeuse, the bright shoulder of Orion, is a third of the way up in the east-southeast at nightfall, to the left of Orion’s Belt. Astronomers have recently detected a possible companion star that appears to be a little bigger and heavier than the Sun.
Moon Phases

At the new Moon phase, the Moon is so close to the Sun in the sky that none of the side facing Earth is illuminated (position 1 in illustration). In other words, the Moon is between Earth and Sun. At first quarter, the half-lit Moon is highest in the sky at sunset, then sets about six hours later (3). At full Moon, the Moon is behind Earth in space with respect to the Sun. As the Sun sets, the Moon rises with the side that faces Earth fully exposed to sunlight (5).
Today’s Sponsor
Stardate Magazine
Current Issue: NOVEMBER/DECEMBER 2025
Meet the Locals
by Kristen Pope
We’ll dig into asteroids, which contain huge amounts of water and precious elements,
and tell you all about the small cluster of galaxies that includes the Milky Way. Merlin will answer your questions, and we’ll have astronomy news, skywatching tips, and more.

Shop
Combos – Bundle and Save
Popular
Explore
Featured Images
Fun Factoid
More fun facts in our Astro Field Guide!
Star Teachers
Stars and Galaxies
Galaxies contain billions of stars. Do galaxies collide? Do the stars within them collide?




