Seleucus of Seleucia was an ancient astronomer who defended heliocentrism, arguing that Earth orbits the Sun and rotates on ...

In March 2025 we have a fine opportunity to view the planet that many astronomy guide books refer to as the most difficult of ...

NASA's Galileo spacecraft took this image of the Moon on December 7, 1992, showing the bright Tycho crater at the bottom. This image, captured by Lunar Orbiter 2, shows Copernicus crater on the Moon ...

In the early seventeenth century, Copernicus' concept of a heliocentric ... to the ground was also responsible for keeping the moon in orbit around the earth, and the planets in orbit around ...

The night sky tonight and on any clear night offers an ever-changing display of fascinating objects you can see, from stars and constellations to bright planets, the moon, and sometimes special ...