Q) A communications satellite launched from Cape Canaveral is placed into a 160

Question

Q) A communications satellite launched from Cape Canaveral is placed into a 160 nautical mile high circular parking orbit inclined at 28.5 degrees to the equator.

a) As the vehicle crosses the equator, the upper stage is reignited to place the satellite into a highly

elliptic 19,432 x 160 nautical mile transfer orbit. Determine the velocity increment needed for this

maneuver.

b) After a final checkout of the satellite, the apogee kick motor is fired on the third apogee to place the

satellite into geosynchronous orbit. Determine the velocity increment needed for this maneuver.

Explanation / Answer

The lower the satellites orbiting the Earth, stronger will be the gravitational pull, and this means that the satellite must travel faster to counteract this pull. Further away the gravitational field is less and the satellite velocities are correspondingly less. For a very low orbit of around 100 miles, a velocity of about 17500 miles per hour is needed and this means that the satellite will orbit the Earth in about 90 minutes. At an altitude of 22 000 miles, a velocity of just less than 7000 miles per hour is needed giving an orbit time of about 24 hours.

Related Questions

Navigate

• Browse (All)
• Browse Q
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.