Day 9 Complete Flashcards
What is the movement of a satellite due to changing mission requirements?
Station Changing
What are small maneuvers needed at regular intervals to keep a satellite in its desired position?
Station Keeping
What is the term for maneuvering a satellite to an unused orbit where it will not affect other active satellites?
Disposal Orbit
What is the term for maneuvering a satellite to reenter the atmosphere and burn up?
De-Orbit
What is changed as a result from Radial Maneuvers?
Argument of Perigee and Eccentricity
What maneuver is similar to hitting the gas or brake in your car, allowing the satellite to speed up or slow down but continue moving in the direction it was already traveling?
In-Track Maneuver
What do in-track maneuvers significantly alter?
The semi-major axis and eccentricity of an orbit
What are ‘out-of-plane’ and alter the inclination of the orbit?
Cross-track maneuvers
What will be affected if a cross-track maneuver is conducted anywhere other than ascending or descending nodes?
RAAN
What will change when conducting a cross-track burn?
Inclination
What requires two in-track maneuvers to move from one circular orbit to another circular orbit?
Hohmann transfer
(most efficient method to change circular orbits)
What is a Simple Plane Change?
An Inclination or RAAN change without changing semi-major axis, eccentricity, or argument of perigee
GSO and LEO costs (m/s)
GSO costs 50 m/s per degree change
LEO costs 130 m/s per degree change
What is a plane change that occurs during the second burn of a Hohmann transfer?
Combined Plane Change
(uses less DeltaV)
What is a satellite or other orbiting body which a spacecraft is attempting to rendezvous with?
Resident Space Object (RSO)
What is a spacecraft that maneuvers to rendezvous with an RSO?
Chaser
What two variables must be known and calculated to complete a rendezvous?
Burn and Timing
What is the difference in mean motion, used to describe how quickly two satellites are moving relative to each other?
Drift Rate
What is a co-orbital rendezvous?
Two satellites in the same orbit with different true anomalies
How does a Chaser that is ahead of a satellite accomplish a rendezvous?
Positive
in-track burn
How can the angular distance between the satellites be altered (catch-up cycle)?
Phasing orbit
NOT to be used in GEO, risk of colliding with another satellite
How does a Chaser that is behind a RSO “catch up”?
Fire a negative in-track burn
(re-circularize with a negative in-track burn)
What is Co-Planar Rendezvous?
Two satellites on the same plane (same Inclination and RAAN, different semi-major axis)
What is required to get the Chaser satellite to the RSO’s orbit (Co-planar)?
Hohmann Transfer
