What is surprising about the planet orbiting the star 51 Pegasi?
A)It has a mass similar to that of Saturn, but its orbital radius is similar to that of Mars.
B)It has a mass almost as large as Jupiter, but its orbital radius is smaller than that of Mercury.
C)Its mass is similar to that of Mercury, but its orbital radius is similar to that of Jupiter.
D)Its mass and orbital radius are almost identical to that of Jupiter, indicating that 51 Pegasi may have a planetary system that is a twin of our own.

Question

Quizplus · Accepted Answer

The planet orbiting the star 51 Pegasi has a mass almost as large as Jupiter, but its orbital radius is smaller than that of Mercury. This is surprising because it was previously thought that giant planets could only form far away from their star due to the lack of materials needed for their formation in the inner regions. This discovery challenged existing theories of planetary formation and led to the development of new ideas like the concept of hot Jupiters.

What Is Surprising About the Planet Orbiting the Star 51