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Low earth orbit, like for the space shuttle or the space station, is about 220 miles up. But there are satellites on higher orbit, like the ones that are geosynchronous. Those are 22500 miles above.

2007-01-25 04:00:42 · answer #1 · answered by Vincent G 7 · 0 0

The lowest range would be a little over a 100 miles. Satellites that low wouldn't last very long due to atmospheric drag - orbits that low were mainly used in the early days for reconaissance satellites that used film for their photographs and had very short missions.

A more common lower range would be around 200 miles. Satellites this low still need periodic boosts to keep them from re-entering the atmosphere (this happened to Skylab when delays in developing the Shuttle resulted in no way provide periodic boosts).

The highest common altitude for operational satellites is about 36,000 km, or about 22,000 miles. This puts a satellite into a geosynchronous orbit. When geosynchronous satellites are about ready to die, they're pushed into a slightly higher orbit (at least 300 to 500 km highers). Geosynchronous satellites are so far above any atmosphere that they remain in orbit virtually forever, so old ones have to be pushed out of the way if you want make sure you always have somewhere to put your new ones.

Our most distant satellites 'around the Earth' would be solar observing satellites (ACE, SOHO, for example), about 1 million miles above the Earth. They're technically not orbiting the Earth, though. They're orbiting the Sun at one of the Lagrange points where their orbit matches the Earth's orbit.

2007-01-25 06:44:11 · answer #2 · answered by Bob G 6 · 0 0

Early Earth orbiting satellites had orbits as low as about 165 km, but the amount of air still at that distance is enough to slow them down a bit so that they reenter after a few days or weeks. The space stations (Skylab, Salyut, Mir, and ISS) orbit(ed) above 300 km which was high enough to keep them aloft for many years, but eventually brought them all down (the ISS is boosted by several km/hr periodically to keep it as high as it needs to be). So, 165 km is about the lowest reasonable orbit.

There are satellites orbiting at many altitudes up to 35,600 km, which is the height for geosynchronous orbits) and there have been satellites orbiting much higher (either for some scientific purpose or some accident). The highest stable orbit would be outside the orbit of the Moon, but not so far out so that the gravity of either Venus or Mars would perturb the satellite.

2007-01-25 05:35:21 · answer #3 · answered by David A 5 · 0 0

How Many Miles To Orbit

2016-11-07 11:15:31 · answer #4 · answered by xochitl 4 · 0 0

a few hundred to a few thousand, depends on what kind of satelite it is and its purpose.

2007-01-25 04:57:30 · answer #5 · answered by Richie B. 2 · 0 0

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The distance between Earth and Pluto varies as the two planets move around their orbits. When they are closest, they are about 29 A.U. apart; at most, the distance is about 51 A.U. Since light travels about 300,000 kilometers each second, it would take light anywhere between 8 hours and 14 hours to make the round-trip journey to Pluto from Earth. Radio signals travel at the same speed as light. If you were using radio signals to control a robot on Pluto, you would have to be very patient. If you sent your robot a command to move, the command would arrive at least 4 hours later. Then, if your robot took a picture and sent it back to Earth, it would take at least 4 more hours before you could see that picture! AU AU, which stands for "astronomical unit", is a unit for measuring distance. One AU is the average distance from the Sun's center to the Earth's center. It is equal to 149,597,871 km (92,955,807 miles). AUs are often more convenient to use than kilometers when measuring large distances such as those in space. In this case kilometers are just too small - it would be like measuring the distance from Boston to San Francisco in inches. AUs simply make a measurement easier to understand and give you something to compare it to. For example, Saturn's orbit around the Sun has an average radius of 9.5 AU, which means that Saturn is about ten times farther from the Sun than Earth is. The average distance from the Sun to distant Pluto is about 40 AU. Mercury, the planet closest to the Sun, orbits at an average distance of 0.39 AU. AUs are generally used for measurements of distances within our Solar System. Distances to stars are much larger, and are expressed in terms of light years. One light year is equal to more than 63,000 AUs. The nearest star, Proxima Centauri, is just over 4 light years away. Although Pluto was discovered in 1930, limited information on the distant planet delayed a realistic understanding of its characteristics. Today Pluto remains the only planet that has not been visited by a spacecraft, yet an increasing amount of information is unfolding about this peculiar planet. The uniqueness of Pluto's orbit, rotational relationship with its satellite, spin axis, and light variations all give the planet a certain appeal. Pluto is usually farther from the Sun than any of the nine planets; however, due to the eccentricity of its orbit, it is closer than Neptune for 20 years out of its 249 year orbit. Pluto crossed Neptune's orbit January 21, 1979, made its closest approach September 5, 1989, and will remain within the orbit of Neptune until February 11, 1999. This will not occur again until September 2226. As Pluto approaches perihelion it reaches its maximum distance from the ecliptic due to its 17-degree inclination. Thus, it is far above or below the plane of Neptune's orbit. Under these conditions, Pluto and Neptune will not collide and do not approach closer than 18 A.U. to one another. Pluto's rotation period is 6.387 days, the same as its satellite Charon. Although it is common for a satellite to travel in a synchronous orbit with its planet, Pluto is the only planet to rotate synchronously with the orbit of its satellite. Thus being tidally locked, Pluto and Charon continuously face each other as they travel through space. Unlike most planets, but similar to Uranus, Pluto rotates with its poles almost in its orbital plane. Pluto's rotational axis is tipped 122 degrees. When Pluto was first discovered, its relatively bright south polar region was the view seen from the Earth. Pluto appeared to grow dim as our viewpoint gradually shifted from nearly pole-on in 1954 to nearly equator-on in 1973. Pluto's equator is now the view seen from Earth. During the period from 1985 through 1990, Earth was aligned with the orbit of Charon around Pluto such that an eclipse could be observed every Pluto day. This provided opportunity to collect significant data which led to albedo maps defining surface reflectivity, and to the first accurate determination of the sizes of Pluto and Charon, including all the numbers that could be calculated therefrom. The first eclipses (mutual events) began blocking the north polar region. Later eclipses blocked the equatorial region, and final eclipses blocked Pluto's south polar region. By carefully measuring the brightness over time, it was possible to determine surface features. It was found that Pluto has a highly reflective south polar cap, a dimmer north polar cap, and both bright and dark features in the equatorial region. Pluto's geometric albedo is 0.49 to 0.66, which is much brighter than Charon. Charon's albedo ranges from 0.36 to 0.39. The eclipses lasted as much as four hours and by carefully timing their beginning and ending, measurements for their diameters were taken. The diameters can also be measured directly to within about 1 percent by more recent images provided by the Hubble Space Telescope. These images resolve the objects to clearly show two separate disks. The improved optics allow us to measure Pluto's diameter as 2,274 kilometers (1413 miles) and Charon's diameter as 1,172 kilometers (728 miles), just over half the size of Pluto. Their average separation is 19,640 km (12,200 miles). That's roughly eight Pluto diameters. Average separation and orbital period are used to calculate Pluto and Charon's masses. Pluto's mass is about 6.4 x 10-9 solar masses. This is close to 7 (was 12 x's) times the mass of Charon and approximately 0.0021 Earth mass, or a fifth of our moon. Pluto's average density lies between 1.8 and 2.1 grams per cubic centimeter. It is concluded that Pluto is 50% to 75% rock mixed with ices. Charon's density is 1.2 to 1.3 g/cm3, indicating it contains little rock. The differences in density tell us that Pluto and Charon formed independently, although Charon's numbers derived from HST data are still being challenged by ground based observations. Pluto and Charon's origin remains in the realm of theory. Pluto's icy surface is 98% nitrogen (N2). Methane (CH4) and traces of carbon monoxide (CO) are also present. The solid methane indicates that Pluto is colder than 70 Kelvin. Pluto's temperature varies widely during the course of its orbit since Pluto can be as close to the sun as 30 AU and as far away as 50 AU. There is a thin atmosphere that freezes and falls to the surface as the planet moves away from the Sun. NASA plans to launch a spacecraft, the Pluto Express, in 2001 that will allow scientists to study the planet before its atmosphere freezes. The atmospheric pressure deduced for Pluto's surface is 1/100,000 that of Earth's surface pressure. Pluto was officially labeled the ninth planet by the International Astronomical Union in 1930 and named for the Roman god of the underworld. It was the first and only planet to be discovered by an American, Clyde W. Tombaugh. The path toward its discovery is credited to Percival Lowell who founded the Lowell Observatory in Flagstaff, Arizona and funded three separate searches for "Planet X." Lowell made numerous unsuccessful calculations to find it, believing it could be detected from the effect it would have on Neptune's orbit. Dr. Vesto Slipher, the observatory director, hired Clyde Tombaugh for the third search and Clyde took sets of photographs of the plane of the solar system (ecliptic) one to two weeks apart and looked for anything that shifted against the backdrop of stars. This systematic approach was successful and Pluto was discovered by this young (born 4 Feb 1906) 24 year old Kansas lab assistant on February 18, 1930. Pluto is actually too small to be the "Planet X" Percival Lowell had hoped to find. Pluto's was a serendipitous discovery. Pluto Statistics Discovered byClyde W. Tombaugh Date of discoveryFebruary 18, 1930 Mass (kg)1.27e+22 Mass (Earth = 1)2.125e-03 Equatorial radius (km)1,137 Equatorial radius (Earth = 1)0.1783 Mean density (gm/cm^3)2.05 Mean distance from the Sun (km)5,913,520,000 Mean distance from the Sun (Earth = 1))39.5294 Rotational period (days)-6.3872 Orbital period (years)248.54 Mean orbital velocity (km/sec)4.74 Orbital eccentricity0.2482 Tilt of axis (degrees)122.52 Orbital inclination (degrees)17.148 Equatorial surface gravity (m/sec^2)0.4 Equatorial escape velocity (km/sec)1.22 Visual geometric albedo0.3 Magnitude (Vo)15.12 Atmospheric composition Methane Nitrogen 0.3

2016-04-10 07:02:32 · answer #6 · answered by Anonymous · 0 0

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