It is amazing how science has enabled us have objects floating in space to support among other things communication on earth. Satellites not only help with communication but also with Astronomy. Newt 4009 lecture 5 has more.
DBS
GSS
MSS
BSS
LEO
MEO
GEO
HEO
LEO
MEO
GEO
HEO
LEO
MEO
GEO
HEO
Elliptical GEO orbit
Circular GEO orbit
Circular MEO orbit
Elliptical MEO orbit
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