On Feb. 18, 1930, Clyde Tombaugh discovered Pluto, at that time classified as the ninth planet.

Trans-Neptunian objects (TNOs) are icy bodies that vary widely in size, from large dwarf planets like Pluto and Eris—each ...

Mars, Venus, Jupiter and Saturn should be visible to the naked eye, but with a telescope you can spot Neptune and Uranus.

For decades, we believed there were nine planets in our solar system—until Pluto was reclassified in 2006. But what if ...

Asteroids that orbit close to the Earth inevitably cause us some anxiety due to the even remote possibility of a collision.

The four planet-strong "planet parade" currently visible to the naked eye in the night sky for a short time after sunset will ...

On this day 35 years ago, NASA's Voyager 1 spacecraft took a picture that changed how we see our planet. The iconic "Pale ...

New findings explain the Phoenix cluster's mysterious starburst. Data confirm the cluster is actively cooling and able to generate a huge amount of stellar fuel on its own.

These popular astronomy questions, answered by Astronomy magazine, will help you better understand our universe - and share ...

Take advantage of a special 6-7 planet alignment from Earth's perspective. Planets 'line up' in the skies over California in ...

For the first time, astronomers have imaged dozens of belts around nearby stars where comets and tiny pebbles within them are ...

Does our Solar System have 9 planets or only 8? Astronomers have gone back and forth on that a lot, with Pluto now being classified as a dwarf planet. However, out beyond Neptune there could be ...