On July 13, 1969, the Soviet Union launched Luna 15, an unmanned spacecraft seen as a rival to the American Apollo 11 mission ...

Venus is notably brighter — magnitude –4.1, far outshining magnitude 0.9 Aldebaran, the brightest star in the Taurus and ...

Several planets stand still in the sky, Titan’s shadow transits Saturn, and Venus gives Taurus a second eye in the sky this ...

Today in the history of astronomy, the most prolific comet-discoverer of all time gets his start.

Algol, also known as the Demon Star, loses some 70 percent of its light every three days. It's in Perseus the Hero, now ...

On his first trip to the Grand Canyon Star Party, Dave Eicher joins thousands for a week of lectures, observing, and cosmic wonder.

Cones outnumber rods only in the center of the retina, which is the area of greatest density. It is also the area most ...

The bright morning star Venus, moving quickly through Taurus, hangs in the predawn sky below the Seven Sisters open cluster.

Quasar 0957+561, the first known gravitationally lensed quasar, lies near NGC 3079 in Ursa Major. Here's how to find and ...

Kluger, who has written about the Apollo Program, talks about his new book: 'Gemini: Stepping Stone to the Moon, The Untold ...

Globular cluster M56 is a gorgeous object in Lyra the Lyre that anyone can observe with binoculars or a telescope.

Inventor Nikola Tesla was born July 10, 1856, in what is now Croatia (then part of the Austrian Empire). In 1899, Tesla ...