Orbital Fundamentals Pg. 1

Question 1

What is the most commonly used orbital regime?

Answer 1

LEO orbits

Question 2

LEO has a period of ( ) to ( ) minutes, and an altitude of how many kilometers?

Answer 2

90-120
2,000

Question 3

MEO has a period of greater than ( ) minutes and less than ( ) hours.

Answer 3

120, 24

Question 4

What three missions does MEO support?

Answer 4

PNT, SATCOM, and Persistent Earth Observation

Question 5

What MEO orbit has a period of about 12 hours?

Answer 5

Semi-Synchronous Orbit (orbit that repeats its ground track every day).

Question 6

What orbits have a period of about 24 hours and altitude of 35,786 km?

Answer 6

GEO orbits

Question 7

What kind of coverage can three satellites in GEO give (exception of polar regions)?

Answer 7

Global

Question 8

What is the orbit where inclination and eccentricity both equal 0?

Answer 8

GEO-Stationary orbit

Question 9

This orbit is a special, near-polar inclination LEO with a retrograde motion.

Answer 9

Sun-synchronous orbit

Question 10

HEO orbits allow max coverage, covering the gap left by what orbits?

Answer 10

GEO orbits

Question 11

What orbits primarily support the missions of SATCOM and Missile Warning.

Answer 11

HEO orbits

(teacher says GEO-synchronous)