Titan Is Roughly the Same Size as Mercury, Yet Titan

question 31

Multiple Choice

Titan is roughly the same size as Mercury, yet Titan has an atmosphere while Mercury does not. How can this be?

• A) Although Titan is roughly the same size as Mercury, it is much denser, making its gravitational field stronger
• B) Unlike Mercury, Titan is constantly being bombarded by icy comets that evaporate and maintain its atmosphere
• C) On its surface, Titan has volcanism that is constantly replenishing its atmosphere while Mercury does not
• D) Even though Titan's gravity is weak, it is much colder, allowing molecules to be trapped in its atmosphere

---

Definitions:

United States

A country in North America consisting of 50 states and a federal district, known for its diverse geography and multicultural population.

Immune Function

The biological processes and mechanisms that enable the body to identify and defend against pathogens, infections, and diseases.

Cerebral Palsy

A neurological disorder that appears in infancy or early childhood and permanently affects body movement and muscle coordination.

Settling-point

A concept in weight regulation theory suggesting that body weight is maintained at a stable level where the factors that increase body weight balance those that decrease it.