The graph below plots the escape velocity of each planet along the vertical axis and its surface temperature along the horizontal. The lines plotted in the figure are the average speeds of gas particles as a function of temperature for various gases. Which of the planets or satellite plotted in this diagram is least able to hold an atmosphere?

Question

Quizplus · Accepted Answer

The ability of a planet/satellite to hold an atmosphere is primarily determined by its escape velocity. The lower the escape velocity, the more easily gas particles can escape the planet's gravitational pull and the less likely it is to retain an atmosphere. In the given graph, the Moon has the lowest escape velocity of all the planets/satellites plotted, indicating that it is least able to hold an atmosphere. The ability of a planet to hold an atmosphere depends on its escape velocity. The higher the escape velocity, the harder it is for gas particles to escape the planet's gravitational pull. From the graph, the Moon has the lowest escape velocity, indicating that it is least able to hold an atmosphere. Additionally, the Moon's surface temperature ranges from very hot during the day to very cold at night, causing significant temperature variations that make it more difficult for an atmosphere to be retained.

The Graph Below Plots the Escape Velocity of Each Planet