What Is Surprising About the Planet Orbiting the Star 51

Multiple Choice

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.