When a comet passes near the Sun, part of it takes on the appearance of a large, bright ball from which the tail extends. This part is called ________.
A) the coma
B) the nucleus
C) the plasma tail
D) the Oort core

Question

Quizplus · Accepted Answer

The coma is the fuzzy cloud-like structure around the nucleus of a comet that becomes visible as the comet gets closer to the Sun. It is the part that takes on the appearance of a large, bright ball from which the tail extends.

Answer: B) the nucleus 
 The nucleus is the solid, rocky, and icy core of a comet that is located at the center of the coma. It is the source of gas and dust that form the coma and the tail.

Answer: C) the plasma tail 
 The plasma tail is the part of the comet's tail that is composed of ionized gas that has been heated by the Sun's energy. It is a long, thin, and curved tail that points away from the Sun.

Answer: D) the Oort core 
 There is no such thing as an Oort core. The Oort cloud is a theoretical region of space beyond the orbit of Neptune where comets are believed to originate from.

When a Comet Passes near the Sun, Part of It