A future news release might report that a new planet has been found around a star very similar to our Sun. The system contains other planets as well like our solar system. This newly discovered planet is claimed to have a mass 40 times that of Earth and is located nearly 25 AU from the star it orbits. Which of the following would be a reasonable prediction about this planet, assuming it formed like our solar system
I.The planet will probably have a mean density of around 5 g/cm3.
II.The planet will probably have a radius of around five to ten times greater than Earth's.
III.The planet will probably have several satellites.
IV.The planet will probably have a composition that is mostly hydrogen and helium.
A)I & IV
B)I, II, & III
C)II, III, & IV
D)I, II, & IV
E)I, II, III, & IV

Question

A future news release might report that a new planet has been found around a star very similar to our Sun. The system contains other planets as well like our solar system. This newly discovered planet is claimed to have a mass 40 times that of Earth and is located nearly 25 AU from the star it orbits. Which of the following would be a reasonable prediction about this planet, assuming it formed like our solar system 
I.The planet will probably have a mean density of around 5 g/cm3.
II.The planet will probably have a radius of around five to ten times greater than Earth's.
III.The planet will probably have several satellites.
IV.The planet will probably have a composition that is mostly hydrogen and helium.
A)I & IV
B)I, II, & III
C)II, III, & IV
D)I, II, & IV
E)I, II, III, & IV

Quizplus · Accepted Answer

II, III, & IVA planet with a mass 40 times that of Earth and located 25 AU from its star is likely to be a gas giant, similar to Jupiter or Saturn in our solar system. Gas giants typically have a composition that is mostly hydrogen and helium (IV), can have several satellites due to their large mass and gravitational influence (III), and have a radius significantly larger than Earth's, though not necessarily five to ten times greater, making (II) a reasonable but slightly exaggerated prediction. They do not have a mean density of around 5 g/cm^3 (I), as that is more characteristic of terrestrial planets.

A Future News Release Might Report That a New Planet