A future news release might report that a new planet has been found around a star very similar to our Sun. 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? A) The planet will probably have about the same radius as Earth. B) The planet will probably have a mean density of around 5 g/cm³. C) The planet will probably have a composition that is mostly hydrogen and helium. D) The planet will probably have liquid water oceans.

Question

Quizplus · Accepted Answer

Given its mass (40 times that of Earth) and its distance from its star (25 AU, similar to Neptune's orbit around the Sun), the planet is likely to be a gas giant, similar to Jupiter or Saturn, which are mostly composed of hydrogen and helium.

A Future News Release Might Report That a New Planet