SSPI Orbital Mechanics & Spacecraft Operations 2

Question 1

What is station-keeping in satellite operations?

Accepted Answer

Performing periodic thruster burns to maintain the satellite's assigned orbital position

Answer

Station-keeping involves regular thruster firings to counteract perturbations such as solar pressure and gravitational effects that cause drift from the assigned orbital slot.

Question 2

What is the approximate one-way signal latency from a ground station to a GEO satellite and back?

Accepted Answer

240–280 milliseconds

Answer

The round-trip distance to GEO (~71,572 km total) divided by the speed of light yields approximately 240–280 ms of propagation delay for a single hop.

Question 3

Which type of orbit is best suited for Earth observation satellites requiring consistent lighting conditions?

Accepted Answer

Sun-synchronous orbit

Answer

Sun-synchronous orbits are designed so the satellite passes over any given point at the same local solar time each day, ensuring consistent illumination for imaging.

Question 4

What is the Molniya orbit primarily used for?

Accepted Answer

High-latitude coverage where GEO satellites have low elevation angles

Answer

Molniya orbits have high inclinations (~63.4°) and high eccentricity, spending most of their ~12-hour period at high northern or southern latitudes, ideal for polar region coverage.

Question 5

What does the term 'apogee' refer to in orbital mechanics?

Accepted Answer

The point in an orbit farthest from Earth

Answer

Apogee is the farthest point from Earth in a satellite's elliptical orbit; the satellite moves slowest at this point according to Kepler's second law.

(SSPI) Society of Satellite Professionals International Certification Practice Test

(SSPI) Society of Satellite Professionals International Certification Practice Test

SSPI Orbital Mechanics & Spacecraft Operations 2