... 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 . ...

... Tonight's Sky . ... The Magazine . ... Star Atlas . ... An artificial comet holds secrets to Earths life . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... The planet has extreme temperature swings and perhaps active lava flows. ... A digital supplement to Astronomy magazine. ... Join TravelQuest International with Astronomy and Discover magazines on one of three great tour options surrounding this celestial spectacle . ... Astronomy Magazine . ...

With this knowledge of orbits, we are ready to plan a trip to Mars. ... The spacecraft will already have the 107,000 kilometers per hour (66,500 miles per hour) speed of Earth, whereas Mars moves at only 86,900 kilometers per hour (53,900 miles per hour). ... A speed of about 42,000 kilometers per hour will be enough to escape the Earth's gravity and, when added to the Earth's orbital speed around the Sun, put the spacecraft on a Hohmann transfer orbit to the Red Planet. ... 1,570,000 . ... Earth . ...

Next: A box, to include Up: To produce a region Previous: To produce a region . select cursor and circle . When in the image window, the mouse now has a box shape with an arrow at the upper left corner. The mouse buttons act as follows: . LEFT - to move the center of the circle at the position of the arrow point. ... RIGHT - idle. center the circle at the point source by positioning the arrow point and clicking on the LEFT mouse button. A circle will appear at the arrow position. ...

Johann Kepler - a Legislator of the Sky. The laws of the planets movements put by Johann Kepler destroyed the thousand year old dogmas about the circles and spheres and opened the way to scientific understanding of celestial occurrences. ... The best object for observation was Mars - its orbit unlike the Earth's one has a noticeable eccentricity, the rotation period in comparison with Jupiter and Saturn is not too long and observation conditions are better than for Mercury and Venus. ...

... 23.02.2011 . ... Credit Copyright: NASA / JHU APL / CIW Explanation: If you looked out from the center of the Solar System, what would you see? ... The Sun's planets all appear as points of light, with the closest and largest planets appearing the brightest. ... MESSENGER, which has flown by Mercury three times now, is on schedule to enter orbit around the Solar System's innermost planet next month. ... Publications with keywords: Solar System . Publications with words: Solar System . ...

... connection points . ... The point P3 is the connection between the horizontal and vertical actuators and is the axis of rotation for the tail gunner motion. processing: survey/020204/reduc We can compute P3,P5 (the moveable points) in dome centerline coordinates if we have the actuator distances and we know the positions of the above connection points in dome centerline coordinates for a given position of the tertiary (say the nominal focus position).(see actuator distances to dome centerline ). ...

... Current APO Weather . ... Search Site . ... Information for New Users . ... Technical Staff pages . Night Logs and Mailing Lists (maintained by APO) . ... Technical Documents and Database Search . ... Observer's Documentation and Procedures . ... Problem Reporting and APO Technical Documents Database Search . ... APO Drawing/Document Management Procedures . ... APO Technical Documents Database Search . Home Astrophysical Research Consortium . ... Mail Lists (maintained by APO) . ...

... The planet in orbit around 51 Peg has, according to theoretical models, moved into its current position from farther away and its atmosphere may therefore be strongly evaporating. The molecules released by the upper parts of the atmosphere must be rapidly ionized and could form an envelope around the planet. If the planet passes in front of the star, this envelope is in favorable geometric conditions (the inclination angle of the orbit is close to 90?) which allow it to occult the star. ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2011 February 23 . The Solar System from MESSENGER . ... Nearly such a view was taken recently from the MESSENGER spacecraft currently orbiting the Sun from the distance of Mercury . ... MESSENGER, which has flown by Mercury three times now, is on schedule to enter orbit around the Solar System's innermost planet next month. ... About APOD | ...

... Next: 7 kslice_3d: slicing data Up: Karma User Manual Previous: 5 Volume Rendering a . The <kpvslice> programme allows you to use a two-dimensional image to define a slice through a three-dimensional data cube. ... The slice is drawn on the total column density or velocity field map, and the corresponding position-velocity diagram will appear in the other window. ... To load the cube, press the Cubes button in the left window and select a cube file. ... The image is displayed in the left window. ...

Microsymposium 38, MS083, 2003 (A4 format) MERCURY: LOCAL VARIATIONS OF THE PHOTOMETRIC RELIEF. ... Because of trajectory and pointing angle constraints the planet could be observed from Mariner 10 only over a small range of phase angles between about 75o and 110o. Therefore the photometric investigations are restricted to measuring the distribution of brightness on the Mercurian disk. ... Raw versions of real-time processing pictures FDS 0000984 and FDS 0000986 were used (images 196 and 202). ...