Question

Choose the correct statement representing the evidence that the planet orbiting 51 Pegasi is a hot Jupiter.

Options:
a) 51 Pegasi is a planet whose orbital period is so short (4 days) that it must lie incredibly close to its star. Furthermore, the size of the stellar Doppler wobble is so large that it must be caused by a planet with at least a mass of 0.6 MJ.
b) 51 Pegasi is a planet whose orbital period is so short (4 days) that it must lie incredibly far from its star. Furthermore, the size of the stellar Doppler wobble is so small that it must be caused by a planet with at least a mass of 0.6 MJ.
c) 51 Pegasi is a planet whose orbital period is so large (50 years) that it must lie incredibly far from its star. Furthermore, the size of the stellar Doppler wobble is so small that it must be caused by a planet with at least a mass of 0.6 MJ.
d) 51 Pegasi is a planet whose orbital period is so large (50 years) that it must lie incredibly close to its star. Furthermore, the size of the stellar Doppler wobble is so large that it must be caused by a planet with at least a mass of 0.6 MJ.

Answer 1

The correct statement is a) 51 Pegasi is a planet with a short orbital period and lies very close to its star, with a large Doppler wobble indicating its significant mass.

Step-by-step explanation:

Given the options to choose the correct statement representing the evidence that the planet orbiting 51 Pegasi is a hot Jupiter, the correct choice is: a) 51 Pegasi is a planet whose orbital period is so short (4 days) that it must lie incredibly close to its star. Furthermore, the size of the stellar Doppler wobble is so large that it must be caused by a planet with at least a mass of 0.6 MJ. This aligns with the findings by Mayor and Queloz, indicating that the planet is indeed very close to 51 Pegasi, completing its orbit in just about 4.2 days. The proximity to its star would significantly heat the planet, classifying it as a hot Jupiter, and the notable Doppler wobble detected is indicative of a planet with considerable mass, at least half the mass of Jupiter, confirming its status as a jovian planet.