... Positions in 2000 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . Positions in 2001 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . Positions in 2002 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . Positions in 2003 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . Positions in 2004 - Jan - Feb - Mar - Apr - May - Jun - Jul - Aug - Sep - Oct - Nov - Dec . ...

... With enough velocity, a spacecraft can break loose from the Earth's gravity and enter an orbit around the Sun, like that of a planet. If it then orbits the Sun with the same period as the Earth--one year--it may keep a fixed position relative to Earth. ... If the distance is just right--about 4 times the distance to the Moon or 1/100 the distance to the Sun--the spacecraft, too, will need just one year to go around the Sun, and will keep its position between the Sun and the Earth. ...

... With enough velocity, a spacecraft can break loose from the Earth's gravity and enter an orbit around the Sun, like that of a planet. If it then orbits the Sun with the same period as the Earth--one year--it may keep a fixed position relative to Earth. ... If the distance is just right--about 4 times the distance to the Moon or 1/100 the distance to the Sun--the spacecraft, too, will need just one year to go around the Sun, and will keep its position between the Sun and the Earth. ...

... More on 51 Peg: . The discovery of a Jupiter--mass planet in orbit around the solar--type star 51Peg has been reported by Michel Mayor and Didier Queloz (Geneva Observatory) on October 6th at the 9th Cambridge workshop on "cool stars, stellar systems, and the sun" held at Florence (Italy). ... Recall that the measurements of radial velocity only yield v sin i which in turn gives us M sin i. For most values of i, sin i will be greater than 0.5 and this gives a mass estimate of 0.5 Jupiter masses. ...

The Discovery of the Galilean Satellites . ... Probably the most significent contribution that Galileo Galilei made to science was the discovery of the four satellites around Jupiter that are now named in his honor. Galileo first observed the moons of Jupiter on January 7, 1610 through a homemade telescope. He originally thought he saw three stars near Jupiter, strung out in a line through the planet. ... Galileo's Observations of Jupiter's Moons . ... Jupiter . ...

Extended ephemerides of NEAs and some unusual minor planets listed in the Table on p. 5731 (Jupiter-crossers, Jupiter-approachers, some unusual Mars-crossers) are presented on p. 23099 – 23489. At the end of the Table special index is placed which indicates page numbers where the ephemerides of different planets are given. ...

In ancient times the solar system was thought to be the whole Universe, so the study of planetary motions was cosmology. ... The planets other than the Moon and Sun generally move West to East through the stars, but occasionally stop and move in the opposite direction ( retrograde motion). In order to explain the retrograde motion of the planets, the geocentric model of the Solar System shown above puts the planets on small circles called epicycles . ...

... Bad Astronomy . Misconceptions . ... Bad Astronomy : The Moon only shows one face to us because it is not rotating. Better astronomy : The Moon only shows one face because it is rotating, once every time it revolves around the Earth. ... Place the Moon model on the table about 30 centimeters (one foot) away with the X facing the Earth model. ... You'll see that to keep the X facing the Earth model, you have to rotate the Moon model as it goes around the Earth model . ... 2008 Phil Plait. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Planets . ... Monthly Sky Notes . ... October . ... By admin October 8, 2010 Posted in: Monthly Sky Notes . A giant from close up: an image made using data from the Cassini probe which flew past Jupiter in 2000. ... As it is so far from us, it takes JupiterтАЩs light a significant time to reach us тАУso when you see Jupiter tonight you are seeing it as it was 35€а minutes in the past. ... Posted October 12, 2010 at 11:15 PM . ... Astronotes . ...