Ground Tracks and Perturbations
Calculating COEs
Maneuvering
Rendezvous
Proximity operations
100
Similar to a geostationary but due to slight variations in inclination and eccentricity, the ground track makes a figure 8.
What is a Geosynchronous Ground Track
100
With these 2 vectors, you can calculate all COEs
What is Position and Velocity
100
Name the 3 reasons to maneuver and brief description
What is Parking orbit- SC cannot launch directly into their orbit, helps save fuel Station change- As mission requirements change, SC location may need to change in its orbital plane Station Keeping- Routine maintenance may be required to keep SC in desired position
100
This is assumed for all Rendezvous because they are most common and fuel efficient
What are Hohmann transfers
100
The Chase satellite must have a reliable relative or terminal _____to complete the maneuver.
What is Guidance System
200
These orbits were designed to take advantage of the J2 Effect.
What is Molniya and Sun Synchronous orbits.
200
This COE uses the eccentricity vector (e) and the satellite's position vector (R)
What is True anomaly
200
Most efficient way to change an orbit
What is Hohmann Transfer
200
Chase satellite starts in____ orbit then continues to it's ____ orbit before reaching the target
What is parking orbit, phasing orbit
200
Cooperative targets ____with the chase vehicle by________, while Non Cooperative targets_____
What is 1. interact 2. provide position and velocity info 3. do not interact or provide info
300
1. As Satellite encounters earths atmosphere, eccentricity becomes closer to _____
What is zero
300
Using the Vernal Equinox (I hat) and the ascending node (n vector), you can find this.
What is RAAN
300
increasing specific mechanical energy will_____ semi major axis Decreasing specific mechanical energy will_____ semi major axis
What is enlarge and reduce. (Equation for potential energy)
300
What are the 2 types of Rendezvous and briefly describe
What is Coplanar- meeting at the target point when both target and chase vehicle are with the same orbital plane. Co-orbital- meeting at a target point when both the target and interceptor are in the same orbit.
300
We use _______coordinate system for chase vehicles and ____coordinate system for target satellites
What is LVLH and RIC
400
Inclinations less than 90 degrees have ______motion Inclinations greater than 90 degrees have ______motion
What is Westward and Eastward.
400
Using northpole (K) and the angular momentum vector (h), you can determine this.
What is inclination (i)
400
This Plane Change maneuver changes the inclination and semi major axis of the orbit, and uses a minimum of 2 burners.
What is Combined Plane Change
400
If the Satellite is behind its target, it will need to do this to reach the target.
What is Slow down
400
________ describes: When the chase satellite will drift forward because of its smaller semi major axis. When a chase satellite drifts backwards because of its larger semi major axis.
What is linear drift
500
Since size of an orbit relates to energy, _____ becomes smaller to atmospheric drag.
What is Semi Major Axis
500
Describe what is needed to calculate specific mechanical energy and each COE.
What is mechanical energy- scalar velocity and scalar position semi major axis- mechanical energy (epsilon) eccentricity- positional and velocity vectors (R and V) inclination- North Pole and angular momentum vector (K and h) RAAN- Vernal equinox and ascending node vector (I and n) Argument of perigee- ascending node and eccentricity/perigee vector (n and e) True anomaly- eccentricity/perigee and position vector (e and R)
500
Describe a fast transfer, and simple plane change maneuver
What is Fast transfer- One tangential burn and one non tangential burn. Simple Plane Change- changes inclination only, and not the size of the orbit.
500
Reasons to Rendezvous include
What is 1. Fill a constellation 2. serve existing satellite 3. inspect an orbiting satellite 4. to intercept (kill or negate) 5. perform defensive maneuvers.
500
These need to be different from the target in order for a loop pattern to occur. These need to be different from the target in order for a corkscrew pattern to occur.
What is: 1. Semi Major axis, and Eccentricity 2. Semi Major axis, eccentricity, and inclination
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