The orbit of Iapetus is somewhat unusual. Although it is Saturn's third-largest moon, it orbits much farther from Saturn than the next closest major moon, Titan. It has also the most inclined orbital plane of the regular satellites; only the irregular outer satellites like Phoebe have more inclined orbits. Because of this distant. A satellite in equatorial orbit flies along the line of the Earth's equator. To get into equatorial orbit, a satellite must be launched from a place on Earth close to the equator. NASA often launches satellites aboard an Ariane rocket into equatorial orbit from French Guyana. These satellites orbit about 23,000 miles (37,015 km) above the equator and complete one revolution around Earth precisely every 24 hours. Satellites headed for GEO first go to an elliptical orbit with an. Geostationary orbit, a circular orbit 35,785 km (22,236 miles) above Earth’s Equator in which a satellite’s orbital period is equal to Earth’s rotation period of 23 hours and 56 minutes. A spacecraft in this orbit appears to an observer on Earth to be stationary in the sky. This particular orbit is.
- Equatorial Orbit Has An Inclination Of
- Equatorial Orbit Satellites
- Equatorial Orbit Define
- Equatorial Orbit Meaning
- Satellite Orbits Explained
A polar orbit is one in which a satellitepasses above or nearly above both poles of the body being orbited (usually a planet such as the Earth, but possibly another body such as the Moon or Sun) on each revolution. It has an inclination of about 60 - 90 degrees to the body's equator.[1] A satellite in a polar orbit will pass over the equator at a different longitude on each of its orbits.
Launching satellites into polar orbit requires a larger launch vehicle to launch a given payload to a given altitude than for a near-equatorial orbit at the same altitude, due to the fact that much less of the Earth's rotationalvelocity can be taken advantage of to achieve orbit. Depending on the location of the launch site and the inclination of the polar orbit, the launch vehicle may lose up to 460 m/s of Delta-v, approximately 5% of the Delta-v required to attain Low Earth orbit. Polar orbits are a subtype of Low Earth orbits with altitudes between 200 and 1,000 kilometers.[1]
Usage[edit]
Polar orbits are often used for Earth-mapping, Earth observation, capturing the Earth as time passes from one point, reconnaissance satellites, as well as for some weather satellites.[2]The Iridium satellite constellation also uses a polar orbit to provide telecommunications services. This differs from a geosynchronous orbit in which one spot on the Earth's surface can be sensed continuously from a satellite.
Sun-synchronous orbits[edit]
Near-polar orbiting satellites commonly choose a Sun-synchronous orbit, meaning that each successive orbital pass occurs at the same local time of day. This can be particularly important for applications such as remote sensing atmospheric temperature,where the most important thing to see may well be changes over time which are not aliased onto changes in local time. To keep the same local time on a given pass, the time period of the orbit must be kept as short as possible, this is achieved by keeping the orbit lower around Earth. However, very low orbits of a few hundred kilometers rapidly decay due to drag from the atmosphere. Commonly used altitudes are between 700 and 800 km, producing an orbital period of about 100 minutes.[3] The half-orbit on the Sun side then takes only 50 minutes, during which local time of day does not vary greatly.
To retain the Sun-synchronous orbit as Earth revolves around the Sun during the year, the orbit of the satellite must precess at the same rate, which is not possible if the satellite were to pass directly over the pole.Because of Earth's equatorial bulge, an orbit inclined at a slight angle is subject to a torque, which causes precession. An angle of about 8° from the pole produces the desired precession in a 100-minute orbit.[3]
See also[edit]
- Vandenberg Air Force Base, a major United States launch location for polar orbits
Equatorial Orbit Has An Inclination Of
References[edit]
- ^ ab'ESA - Types of Orbits'. 2020-03-30. Retrieved 2021-01-10.
- ^Science Focus 2nd Edition 2, pg. 297
- ^ abStern, David P. (2001-11-25). 'Polar Orbiting Satellites'. Retrieved 2009-01-21.
External links[edit]
- Orbital Mechanics (Rocket and Space Technology)
Three Classes of Orbit
Equatorial Orbit Satellites
Equatorial Orbit Define
High Earth Orbit
Equatorial Orbit Meaning
When a satellite reaches exactly 42,164 kilometers from the center of the Earth (about 36,000 kilometers from Earth’s surface), it enters a sort of “sweet spot” in which its orbit matches Earth’s rotation. Because the satellite orbits at the same speed that the Earth is turning, the satellite seems to stay in place over a single longitude, though it may drift north to south. This special, high Earth orbit is called geosynchronous.
Satellite Orbits Explained
A satellite in a circular geosynchronous orbit directly over the equator (eccentricity and inclination at zero) will have a geostationary orbit that does not move at all relative to the ground. It is always directly over the same place on the Earth’s surface.
A geostationary orbit is extremely valuable for weather monitoring because satellites in this orbit provide a constant view of the same surface area. When you log into your favorite weather web site and look at the satellite view of your hometown, the image you are seeing comes from a satellite in geostationary orbit. Every few minutes, geostationary satellites like the Geostationary Operational Environmental Satellite (GOES) satellites send information about clouds, water vapor, and wind, and this near-constant stream of information serves as the basis for most weather monitoring and forecasting.