• Thumbnail for Orbit of the Moon
    The Moon orbits Earth in the prograde direction and completes one revolution relative to the Vernal Equinox and the stars in about 27.32 days (a tropical...
    37 KB (4,652 words) - 18:08, 16 April 2024
  • Thumbnail for Moon
    The Moon is Earth's only natural satellite. It orbits at an average distance of 384,400 km (238,900 mi), about 30 times the diameter of Earth. Over time...
    256 KB (24,770 words) - 09:05, 9 May 2024
  • Thumbnail for Lunar orbit
    spaceflight, a lunar orbit (also known as a selenocentric orbit) is an orbit of an object around Earth's Moon. In general these orbits are not circular....
    16 KB (1,730 words) - 18:59, 18 April 2024
  • Thumbnail for Halo orbit
    for orbits around L2 which were made periodic using thrusters. Farquhar advocated using spacecraft in such an orbit beyond the Moon (Earth–Moon L2) as...
    11 KB (1,104 words) - 16:53, 22 April 2024
  • Thumbnail for Earth's orbit
    Sun or Moon diameter every 12 hours). Earth's orbital speed averages 29.78 km/s (107,200 km/h; 66,620 mph), which is fast enough to cover the planet's...
    17 KB (1,834 words) - 05:28, 17 March 2024
  • Thumbnail for Moon landing
    A Moon landing or lunar landing is the arrival of a spacecraft on the surface of the Moon, including both crewed and robotic missions. The first human-made...
    115 KB (10,773 words) - 08:05, 9 May 2024
  • the Sun, shift. The visible side of the Moon is sunlit to varying extents, depending on the position of the Moon in its orbit, with the sunlit portion...
    25 KB (2,708 words) - 00:25, 1 May 2024
  • Thumbnail for Moons of Saturn
    There are 146 moons with confirmed orbits, the most of any planet in the solar system. This number does not include the many thousands of moonlets embedded...
    159 KB (9,948 words) - 01:00, 4 March 2024
  • Thumbnail for Lagrange point
    gravitational influence of two massive orbiting bodies. Mathematically, this involves the solution of the restricted three-body problem. Normally, the two massive...
    50 KB (5,703 words) - 21:56, 7 May 2024
  • Thumbnail for Apollo program
    one-quarter of the population of the world saw—either live or delayed—the Christmas Eve transmission during the ninth orbit of the Moon, and an estimated...
    150 KB (15,935 words) - 21:37, 24 April 2024