Simple math really. What is the Spees of an object moving with same speed as earth moves if we kept the object in centre of earth in equator. If the object your are referring to is at the absolute centre of the earths rotation it has no speed. But this is only if the said object has no size or diameter itself, I.
E the perfect centre of rotation. If the object your talking of has any size at all it will have a definate surface speed at whatever the radius you believe your object to be. All speeds must be related to another object. Typically, orbital "speeds" are expressed in relation to the center of the object planet, star being orbited.
Some commenters seem to be relating the orbits to the surface of the Earth, not its center. In relation to the Earth's center, these orbits must be That makes the circle they cover equal to two Pi times In twenty-four hours, that speed is about 6. Post a Comment. Geostationary orbit: Are satellites faster than the space shuttle? July 29, Two colleagues and I went out for lunch today and one of them asked what the word 'geosynchronous' meant.
It's a term to describe the orbit of a satellite that appears to be stationary over the Earth, we answered, and then we all three pushed our imaginary glasses up the bridge of our noses. We were half right with our explanation. Geosynchronous is a term used to describe the orbit of a satellite that moves at the same speed that the Earth rotates about its axis. However, because this orbit can be titled over the Earth like an angel with a lopsided halo, the satellite can appear to move north and south in the sky throughout the day, though it always stays over the same line of longitude.
A geostationary orbit, the one we often think of when we hear the word "geosynchronous," is when a satellite is in a geosynchronous orbit over the equator.
In this kind of orbit, the satellite appears to be stationary over the Earth. In the same way that a square is always a rectangle but a rectangle isn't always a square, a satellite in a geostationary orbit is always in a geosynchronous orbit, but not the other way around.
At the correct orbital velocity, gravity exactly balances the satellite's inertia, pulling down toward Earth's center just enough to keep the path of the satellite curving like Earth's curved surface, rather than flying off in a straight line.
The orbital velocity of the satellite depends on its altitude above Earth. The nearer to Earth, the faster the required orbital velocity. At an altitude of miles kilometers , the required orbital velocity is a little more than 17, mph about 27, kph. To maintain an orbit that is 22, miles 35, kilometers above Earth, the satellite must orbit at a speed of about 7, mph 11, kph.
That orbital speed and distance permit the satellite to make one revolution in 24 hours. Since Earth also rotates once in 24 hours, a satellite at 22, miles altitude stays in a fixed position relative to a point on Earth's surface.
Because the satellite stays right over the same spot all the time, this kind of orbit is called "geostationary. In general, the higher the orbit, the longer the satellite can stay in orbit. At lower altitudes, a satellite runs into traces of Earth's atmosphere, which creates drag.
Soon after, Sputnik 2 carried the first living passenger into orbit, a dog named Laika. In , the United States launched its first satellite, Explorer 1. A year later, NASA's Explorer 6 sent the first satellite pictures of Earth, and by , the first orbiting satellite provided long-term service to the Earth. Since that time, the number of satellites and their complexity has continued to increase.
Since , more than 8, satellites from more than 50 countries have been launched. Today, about 3, man-made satellites remain in orbit, with about 1, of them currently functioning. If you go outside on a clear night and see a bright light speeding across the sky, it may well be a satellite reflecting the light of the Sun. Satellites come in many shapes and sizes.
They can be as small as your hand or as large as a truck. But most have similar parts. The bus, or container, is the main body of the satellite. Attached to the bus are antennas that receive and send signals back to Earth. Because satellites have to power themselves, they all have a power source, usually solar panels or batteries. Earth-orbiting satellites have instruments, such as cameras and sensors, that are pointed toward Earth to gather information about our planet.
Other satellites have instruments facing toward space to collect data from the solar system and universe. Most artificial satellites orbit the earth, but some orbit other planets, such as Mars, Venus, and Saturn, and still others orbit the Sun.
Some satellites help people send information around the world. Information from a ground station on Earth can be sent to an orbiting satellite that bounces it back to receivers at another location on Earth. Other types of satellites take pictures or gather data about our planet and send that data back to Earth.
Satellites in space help us overcome the limitations of Earth's geography. They can collect and send more information, more quickly, than instruments on the ground.
Satellites are launched into space on rockets. How do they stay in orbit? A satellite orbits Earth when its speed is balanced by the pull of Earth's gravity. Without this balance, the satellite would fly in a straight line off into space or fall back to Earth. Orbital velocity is the speed needed to achieve balance between gravity's pull on the satellite and the satellite's tendency to keep going.
At the correct orbital velocity, gravity pulls down toward Earth's center just enough to keep the path of the satellite curving like Earth's curved surface. The orbital velocity of the satellite changes depending on its altitude above Earth. Those satellites that are closer to the earth must move faster to stay in orbit. The higher the orbit, the longer the satellite can stay in orbit.
At lower altitudes, traces of Earth's atmosphere create drag , which sometimes causes the orbit to change. At higher altitudes, where there are no traces of atmosphere, a satellite can stay in orbit for centuries.
Can satellites collide in space? It's possible. NASA and other international organizations keep track of satellites in space. When a satellite is launched, it is placed into an orbit designed to avoid other satellites. But orbits can change over time, and with more satellites, the chance of a crash increases. In , an American satellite and a Russian satellite accidentally collided in space. Watch NASA scientists avert a close call between two satellites.
When it comes to satellites, it's all about the orbit. Space scientists decide on the orbit for a satellite depending on its job.
Some satellites orbit at a low altitude, just a few hundred miles above the Earth. If a player could throw the ball hard enough so that it reaches the necessary velocity, the ball would go into orbit. It would never fall back to Earth. Throw it harder still, so that it reaches a speed of
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