Name two primary propulsion types used for orbital maneuvers.

Name two primary propulsion types used for orbital maneuvers.

• A. Nuclear propulsion and chemical propulsion
• B. Chemical propulsion and electric propulsion
• C. Gravity assist and ion propulsion
• D. Solar sail and chemical propulsion

Answer: (B)

Two main ways spacecraft achieve changes in velocity for orbital maneuvers are chemical propulsion and electric propulsion. Chemical propulsion uses the energy released from chemical reactions in propellants to produce a large thrust in short bursts. That high-thrust capability is ideal for impulsive maneuvers like rapid burns to insert into an orbit, perform a plane change, or deorbit, where you need a strong push in a brief moment.

Electric propulsion instead uses electricity to accelerate propellant to much higher exhaust speeds, giving a very high specific impulse but relatively low thrust. This makes it efficient for long-duration, gradual delta-v changes, such as orbit raising, long-term station-keeping, or deep-space cruise, where conserving propellant mass is valuable even though the maneuver takes longer.

Other options like gravity assists involve changing velocity through gravitational interactions rather than producing thrust, and solar sails rely on photon pressure rather than conventional propulsion. Nuclear propulsion exists conceptually but is not a standard method used for typical orbital maneuvers.