Question

Which of the following statements about Pluto's atmosphere is FALSE?

1) 1) it is currently at its maximum, since Pluto is closest to the Sun
2) 2) it is made of a mixture of nitrogen and methane gas
3) 3) it extends out to the orbit of Charon, where we can still measure it
4) 4) the pressure at the surface is about a ten-thousandth of Earth's
5) 5) much of it will freeze out when Pluto is in that part of its orbit which is much more distant from the Sun

Answer 1

The FALSE statement about Pluto's atmosphere is that it extends out to the orbit of Charon, which is not supported by current observations. Pluto's atmosphere is a mixture of nitrogen and methane gas and reaches a maximum when Pluto is closest to the Sun.

Step-by-step explanation:

The statement that is FALSE about Pluto's atmosphere is: 3) it extends out to the orbit of Charon, where we can still measure it. Pluto's atmosphere does not extend out to the orbit of its moon Charon, but instead consists of a mixture of nitrogen and methane gas that creates a tenuous atmosphere around the planet itself. When Pluto is closest to the Sun, this atmosphere is at its maximum, as the higher temperatures allow for sublimation of nitrogen and methane ices on the surface, forming a gaseous envelope. Even at this point, the surface pressure of the atmosphere is around a ten-thousandth of Earth's atmospheric pressure. The statement about the atmosphere reaching out to the orbit of Charon is not supported by scientific observations.

The other statements about Pluto's atmosphere are consistent with our current understanding. The atmosphere is indeed made of a mixture of nitrogen and methane gas (2). When Pluto is closest to the Sun, its atmosphere thickens due to the partial sublimation from solid to gas form of methane and nitrogen ice (1). The surface pressure is indeed roughly a ten-thousandth of Earth's (4), and much of Pluto's atmosphere is expected to freeze out when it moves into further parts of its orbit away from the Sun (5).