Hubble’s greatest hits

The world’s favorite orbiting observatory has transformed our knowledge about exoplanet atmospheres, the fate of the universe, and almost everything in between.

How the Ritchey-Chrétien telescope was born

George Ritchey had great vision and skill. Henri Chrétien was a brilliant astronomer and optical engineer. Together, they created one of today’s best telescope designs.

Do all galaxies have dark matter?

The discovery of two ghostly galaxies created quite a hullabaloo in the astronomical community. But the jury’s still out on what’s really going on.

Secrets of the Northern Pinwheel Galaxy

Think you know the big spiral M101? Take a deep dive into its myriad details, and you’ll know it like never before.

Explore the Moon at First Quarter

If you’re just starting out, our natural satellite makes a tempting target in the evening sky.

Run a Messier marathon

Seeing all 109 objects in one night should be on your observing bucket list.

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