Which one of the following statements best reflects the idea behind the "Fractional Orbital Bombardment System" often talked about in media?

A A hypersonic missile is launched into space to counter the asteroid approaching the Earth and explode it in space.

B A spacecraft lands on another planet after making several orbital motions.

C A missile is put into a stable orbit around the Earth and deorbits over a target on the Earth.

D A spacecraft moves along a comet with the same speed and places a probe on its surface.

Correct answer: (c) A missile is put into a stable orbit around the Earth and deorbits over a target on the Earth.

Explanation

A
A hypersonic missile is launched into space to counter the asteroid approaching the Earth and explode it in space.
Hypersonic vs asteroid. Planetary defence, not FOBS.
B
A spacecraft lands on another planet after making several orbital motions.
Landing on another planet. Ordinary interplanetary flight.
C
A missile is put into a stable orbit around the Earth and deorbits over a target on the Earth.
A warhead placed in a fractional Earth orbit and deorbited onto a target. That is FOBS.
D
A spacecraft moves along a comet with the same speed and places a probe on its surface.
Comet rendezvous. Science mission, not bombardment.

Summary. Official key is (c). Fractional Orbital Bombardment System puts a payload into a partial Earth orbit and brings it down on a target — the path China tested in 2021 coverage. It is not asteroid defence, a planetary landing, or a comet probe.

← 2022 Set A paper