There are three general classes of orbit that may be suitable for small satellites the geostationary orbit (GSO), the highly elliptical orbit (HEO) and the low Earth orbit (LEO).

Basic orbital parameters Geostationary orbit

Basic orbital parameters Geostationary orbit

The geostationary orbit

(Geostationary orbit)

In the United States, four groups of such satellites are deployed, namely, communications intelligence (COMINT) in the geostationary orbit (GSO) and signals or electronic intelligence (ELINT) satellites in the GSO and in high elliptical Earth (HEO) and low Earth (LEO) orbits.

B. Geostationary orbit 32 39 6

For that purpose, mainly three modes of operations were developed first a tracking mode of operation to measure selected objects in low Earth orbit, in geosynchronous orbit and in geostationary transfer orbit.

2. The spacing between GEO and the graveyard orbit

GTO upper stage deorbit

GEO satellite deorbit after EOL and

It has a fairly substantial number of asteroids between the orbit of the Earth out through to the orbit of Jupiter.

from a low intensity collision in GEO graveyard orbit (bottom)

(c) Disposition of the objects on geostationary transfer orbit so as not to pose a risk to the geostationary orbit

For that, mainly three modes of operation were developed a tracking mode of operation to measure selected objects in low Earth orbits (LEO), in geosynchronous orbits (GSO), and in geostationary transfer orbits (GTO).

(h) Upper stages used to transfer geostationary spacecraft from geostationary transfer orbit to geostationary orbit should, on completion of the mission, be inserted into a disposal orbit that has a perigee at least 300 km above the geostationary orbit

It utilizes LEO store and forward satellites in polar orbit.

38. The following ESA geostationary satellites have been reorbited so far OTS 2 (orbiting at 318 kilometres above GSO), GEOS 2 (260 kilometres), Meteosat 2 (334 kilometres), ECS 2 (335 kilometres) and Olympus 1 (because of a failure, this satellite has been left in an orbit 213 kilometres below GSO).

The minimum diameter of observable objects was about 10 centimetres for LEO and 1 metre for geostationary satellite orbit (GSO).

The model is applicable to altitudes from LEO to GEO, providing environment estimates in the short term.

A. Low Earth and highly eccentric orbits 22 31 5

The following ESA geostationary satellites have been re orbited OTS 2 (orbiting 318 km above GSO), GEOS 2 (260 km), Meteosat 2 (334 km), ECS 2 (335 km) and Olympus 1 (due to a failure, this satellite has been left at orbit 213 km below GSO).

(i) The geostationary orbit location, where appropriate

III. ENVIRONMENTAL PROTECTION OF THE GEOSTATIONARY ORBIT 21 27 5

IV. ENVIRONMENTAL PROTECTION OF THE GEOSTATIONARY ORBIT 30 37 7

IV. ENVIRONMENTAL PROTECTION OF THE GEOSTATIONARY ORBIT

GEO satellites were also designed and operated to conduct reorbit manoeuvre at the end of the mission to preserve the GEO environment. F. Conclusion

The upper stages or components of launch vehicles left in GTO may be manoeuvred to prevent interference with systems in GEO.

Preservation of the environment of Low Earth Orbit (LEO) is also important because of its usefulness for various missions such as Earth observation and satellite communication.

The upper stages or components of launch vehicles left in GTO may be either soon removed from orbit or, if removal is not possible, manoeuvred to prevent interference with systems in GEO.

The current network includes six satellites in geostationary orbit and three in polar orbit.

However, for objects in high Earth orbit (HEO), such as those in geosynchronous orbit, observations can often be continued during the entire night.

Preservation of the environment of the Geostationary Orbit (GEO) is particularly important because natural forces cannot clean up the debris in GEO

Relocation of space objects in Geostationary Transfer Orbit (GTO) to prevent collision with space objects in GEO

For example, the transfer of geostationary orbit (GEO) spacecraft to orbits above GEO not only protects operational spacecraft but also reduces the probability of derelict objects colliding with one another and creating debris that might threaten the GEO regime.

For example, the transfer of geostationary orbit spacecraft to orbits above GEO not only protects operational spacecraft but also reduces the probability of derelict objects colliding with one another and creating debris that might threaten the GEO regime.

The United States deploys them in the GSO.

C. Geostationary orbit communication satellite programmes

The impact characteristics, however, vary considerably between target satellites in GEO and in IGSO.

The minimum size of detectable objects would be 2 6 centimetres in LEO and 20 40 centimetres in GSO.

2.2.2 Collision risk assessments in low Earth orbit

Whereas geostationary satellites used to spend the last remaining fuel to leave GEO and reach the highest possible graveyard orbit, IGSO satellites should expend their fuel to change their orbital parameters in a way that leads to a minimum remaining time in the nominal orbit and, if possible, to an early re entry into the Earth atmosphere.

Reorbiting of spacecraft from GEO to other orbit after their mission

Using this procedure the SMS 1 satellite was put into disposal orbit 500 km above GSO, SMS 2 about 245 km above GSO and GOES 4 about 277 km above GSO.

In particular, no information is available in the regions of highest density of space debris in LEO (at an altitude of about 800 1000 kilometres) as well as in the geostationary orbit.