Am I correct in saying that all TV satelites are in Geostationary orbit?

Question

Is it true that all geostationary satelites are over the equator?
If that is so then their altitude is just governed by their mass?
Would it therefore be true that a satelite broadcasting to Europe would have to be higher than one broadcasting to Egypt, say, in order to see over the horizon

Answer 1

All television satellites are in Geostationary Orbit which is why you can view them from a dish that you don't have to move.

In order to acheive geo-statoary orbit, the satellite needs to be in a space that is approximately 50km cubed. The satellites actually have small rocket boosters attached to 'correct' their position if necessary.

The wikipedia link below gives some in-depth information on how the positions are calculated.

Answer 2

Yes, no and no in that order.

Geostationary orbits must be over the equator. A geostationary orbit requires a rotation rate the same as Earth's (i.e. on revolution per 24 hours). At anywhere other than over the equator this cannot allow the satellite to sit over one point on the Earth's surface, since the orbital plane must intersect the centre of the planet.

The altitude of the satellite, however, is not governed by its mass. In fact, the mass of the satellite is irrelevant. Altitude in orbit is related to the mass of the planet and the speed of the satellite. Doing the required calculations shows that a geostationary orbit can only be maintained at an altitude of about 22,000 miles. That's more than twice the diameter of the planet. At that altitude about one half of the planet is visible to the satellite (though the signal tends to get to spread out at the extreme edges, and is therefore not so good for these areas). Europe and Egypt are equally well visible to the satellite from up there.

Answer 3

1. All TV satellites are in geostationary orbit. They are all positioned at some longitude over the equator (so as to cover the part of the earth they need to cover)

2. The altitude is not governed by mass, as the most massive TV satellite is still negligible compared with the mass of the Earth. The altitude is governed by the mass of the Earth and the velocity of the satellite (see that Wiki article listed in an answer, above)

3. A TV satellite orbiting at longitude 15 degrees East (over the equator, of course), is at such a great height that it can 'see' Egypt and all of Europe (with the exception of some of the far northern parts of the scandinavian countries). A receiver in Egypt will have to point their antennas almost vertically, while a receiver in Oslo will have to point their antenna almost horizontally (and it will be easier for trees, buildings, etc., to block the signal).

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Answer 4

Yes, all TV satellites are in geostationary orbit.

Yes, geostationary orbit is always directly over the equator.

No, their altitude is not governed by their mass. It is governed by the mass of the Earth and the rotation rate of the Earth. In other words is is a property of the Earth and not the satellite.

No, a satellite broadcasting to Europe would not have to be higher than one broadcasting to Egypt. Geostationary orbit is so high that the satellites can see about 1/3 of the Earth in one view. I calculate that from geostationary orbit a single satellite can see all the way from 81 degrees north to 81 degrees south latitude in one view.

Answer 5

Yes, all geostationary orbits are over the equator. But the altitude of the geostationary orbit is not affected by the mass of the sattelite, unless the mass of the sattelite begins to approach the mass of the Earth itself!! It is the mass of the Earth that defines the accelertion on an object, so objects of ALL masses experience the same acceleration.

And the altitude of a geostationary orbit is 35,786 km, so the "horizon" for such a sattelite occurs at about the 80 deg latitude line. Considering the arctic circle is at the 67 deg latitude line, I think 80 deg coverage is sufficient.

Answer 6

The early TV satellites like Telstar were in low earth orbit and so could only relay signals between earth stations for a short time each time round. TV satellites in use now are in geostationary orbit, meaning they stay above a fixed point on the equator. To cover different areas of the earth's surface, satellites are positioned at different longitudes (east and west).

Answer 7

Yes, the satellites are in an orbit that follows the line of the equator and at a height and velocity that is the same as the earth's rotation, so they appear to be "Stationary" over the equator. That is why satellite dishes in England have to point south, towards the equator.

A satellite dish in Brazil therefore is pointing straight up and those in Canada are much larger (about a metre) as the satellite is farther away and the signal is attenuated.

Answer 8

Most TV satellites are in geosynchronous orbits.
They are at an altitude of about 220,000 miles.
They service the greater part of the earth.
The signal [foot print] in extreme northern areas,like parts Russia these areas are out of range.
Over the north pole there are four satellites in highly elliptical orbits that are switched on and off to give a steady TV grade signal to these northern areas.
They aren't well known but they are there.

Answer 9

Yes,you're spot on !!