From: Amara Graps (amara@amara.com)
Date: Fri Mar 01 2002 - 06:30:53 MST
the animated silicon love doll:
> >and GEO (esp. debris 'clouds' as a result of firings from solid rocket
>
>I don't dare google "geo" because I know I will get plenty that is not what
>I'm looking for (stupid cars)...
>So would I be right in assuming that this stands for Geosynchronous Earth
>Orbit?
Yes, or just geosynchronous orbit ("geo" refers to Earth already)
Some common terms
GEO = geosynchronous orbit (6.6 * R_earth)
GSO = geostationary orbit (6.6 * R_earth)
LEO = low-earth orbit (say < 2 * R_earth)
See:
http://www.celestrak.com/columns/v04n07/
for text and the figures
A.C. Clarke was such a pioneer ...! He originated the idea of using
the GSO for communications.
See Arthur C. Clarke's figure (above URL) from his article in the
October 1945 edition of Wireless World.
More from the above URL:
{begin quote}
For any orbit to be geostationary, it must first be geosynchronous.
A geosynchronous orbit is any orbit which has a period equal to the
earth's rotational period. As we shall soon see, this requirement is
not sufficient to ensure a fixed position relative to the earth.
While all geostationary orbits must be geosynchronous, not all
geosynchronous orbits are geostationary. Unfortunately, these terms
are often used interchangeably.
[...]
To ensure that a satellite remains over a particular point on the
earth's surface, the orbit must also be circular and have zero
inclination. Figure 2 shows the difference between a geostationary
orbit (GSO) and a geosynchronous orbit (GEO) with an inclination of
20 degrees. Both are circular orbits. While each satellite will
complete its orbit in the same time it takes the earth to rotate
once, it should be obvious that the geosynchronous satellite will
move north and south of the equator during its orbit while the
geostationary satellite will not.
[...]
It should now be apparent that only satellites which orbit with a
period equal to the earth's rotational period and with zero
eccentricity and inclination can be geostationary satellites. As
such, there is only one geostationary orbit-a belt circling the
earth's equator at an altitude of roughly 35,786 kilometers. {end quote}
-- ************************************************************************ Amara Graps, PhD | Max-Planck-Institut fuer Kernphysik Heidelberg Cosmic Dust Group | Saupfercheckweg 1 +49-6221-516-543 | 69117 Heidelberg, GERMANY Amara.Graps@mpi-hd.mpg.de * http://www.mpi-hd.mpg.de/dustgroup/~graps ************************************************************************ "We came whirling out of Nothingness scattering stars like dust." --Rumi
This archive was generated by hypermail 2.1.5 : Sat Nov 02 2002 - 09:12:43 MST