Three terrestrial-sized planets in orbits of a fraction of an A.U. have been found near:
A)Cygnus X-1.
B)a magnetar.
C)Supernova 1987A.
D)a millisecond pulsar.
E)a white dwarf.

Question

Quizplus · Accepted Answer

Terrestrial-sized planets are typically found in close proximity to millisecond pulsars, which are rapidly rotating neutron stars. The intense gravitational forces near these stars can create stable, short-period orbits for the planets. The other options (A, B, C, E) all involve objects that would not be conducive to planet formation and would likely disrupt any existing planets. Terrestrial-sized planets are typically found in orbits close to their host stars. Millisecond pulsars are rapidly-spinning neutron stars that emit regular pulses of radiation, and they can have planets in close orbits due to their small size and high mass. Therefore, it is the best choice for finding terrestrial-sized planets in orbits of a fraction of an A.U.

Three Terrestrial-Sized Planets in Orbits of a Fraction of an A.U