LYCOS RETRIEVER 
Satellites: Orbits
built 280 days ago
This four-picture sequence (spanning 30 minutes) shows one of four new satellites discovered by the Hubble Space Telescope, in images taken of Saturn on May 22, 1995. This satellite is identified as S/1995 S3 and appears as an elongated white spot near the center of each image. The new satellite lies just outside Saturn's outermost "F" ring and is no bigger than about 15 miles across. The brighter object to the left is the moon Epimetheus, which was discovered during the ring-plane crossing of 1966. Both moons change position from frame to frame because they are orbiting the planet.
Source:
This discussion can lead to an opportunity to present the notions of geostationary and polar-orbiting satellites. The notion of polar-orbiting satellites(those whose orbits take them above both poles)may be easier for students to understand. They seem to understand the notion of the ground track of polar-orbiting satellites. The reason may be that the movement of these satellites is similar to that of an airplane in the sky. Thus, presenting the polar-orbiting notion first may be desirable. The class discussion will determine if this seems appropriate.
Source:
The A-Train is a set of 5 satellites that are planned to orbit in the same orbital plane one after the other in pretty close spacing. It is approximately 15 minutes from the front satellite to the rear satellite and some of them are within a minute of each other. The A-Train is led by the Aqua satellite. Next are CloudSat and CALIPSO followed by Parasol and then Aura pulling the rear. All five satellites cross the equator within a few minutes of one another at around 1:30 pm (13:30) local time. Since these satellites are flying in tandem, the set of satellites is referred to as a constellation, or alternatively, as a formation.
Source:
Space shuttles carry some satellites into space, but most satellites are launched by rockets that fall into the ocean after their fuel is spent. Many satellites require minor adjustments of their orbit before they begin to perform their function. Built-in rockets called thrusters make these adjustments. Once a satellite is placed into a stable orbit, it can remain there for a long time without further adjustment.
Source:
There are five major Uranian satellites (left to right in mosaic: Miranda, Ariel, Umbriel, Titania, and Oberon). They range from ~470 to 1600 kilometers across. They are composed of roughly equal mixtures of water and other ices and rocky material. Umbriel and Oberon are heavily cratered and Titania has a few large fractures. Miranda and Ariel have surprisingly complex geologic histories for such small bodies, the reasons for which are not well understood, but are probably related to tidal heating. At least 10 small satellites orbit near Uranus' thin ring system.
Source:
The idea of using satellites for navigation began with the launch of Sputnik 1 on October 4, 1957. Monitoring that satellite, scientists at Johns Hopkins University's Applied Physics Laboratory noticed that when the transmitted radio frequency was plotted on a graph, a curve characteristic of the Doppler shift appeared. By studying this apparent change of radio frequency as the satellite passed overhead, they were able to show that the Doppler shift, when properly used, described the orbit of the satellite.
Source:
MORE ABOUT
Orbits