Become an expert stargazer—in one week

National Geographic's Wonder Lessons will teach you how to navigate the stars, spot cloud types, identify common trees, and catalogue different rocks. Today, we're learning about how to find the constellation Gemini.

ByStephanie Vermillion
Published April 9, 2026

As with many constellations, it’s trickier to spot Gemini’s entire shape in light-polluted areas—but this month we have some extra navigational help.

The two brightest stars in this constellation are Castor and Pollux. In April, luminous Jupiter, usually the second brightest planet in the night sky, appears below Castor and Pollux, forming a triangle with Gemini’s most visible stars.

Tip: Pollux is the brighter of the two stars and has a more golden hue, while Castor is dimmer. While less bright than Pollux, Castor is actually a system of six gravitationally bound stars orbiting each other.

See if you can find the night sky's twins. 

Want to experience more wonder? National Geographic's Wonder List features playful prompts and activities that turn everyday moments into wonder-filled discoveries—for families, anywhere, every day.

Star maps: Matthew W. Chwastyk, NG Staff.
Sources: Tycho Catalog Skymap, NASA/Goddard Space Flight Center Scientific Visualization Studio