# mesosphere

## mesosphere

Above the stratosphere is the mesosphere. Temperatures in the mesosphere decrease with altitude. Because there are few gas molecules in the mesosphere to absorb the Suns radiation, the heat source is the stratosphere below. The mesosphere is extremely cold, especially at its top, about -90o C (-130o F).

## air density

The air in the mesosphere has extremely low density: 99.9% of the mass of the atmosphere is below the mesosphere. As a result, air pressure is very low (Figure 1.1). A person traveling through the mesosphere would experience severe burns from ultraviolet light since the ozone layer, which provides UV protection, is in the stratosphere below. There would be almost no oxygen for breathing. And, of course, your blood would boil at normal body temperature. Click image to the left or use the URL below. URL:

## instructional diagrams

No diagram descriptions associated with this lesson

## questions

the pressure in the mesosphere is so low that the liquids would boil at normal body temperature.

``````-->  a) true

b) false
``````

meteors burn up in the mesosphere. how can this happen?

``````a) the mesosphere is so hot (remember, your blood would boil) that it burns up.

-->  b) a meteor travels so fast that it experiences friction from a lot of air molecules.

c) meteors burn up when they run into the clouds found in the mesosphere.

d) a & b
``````

although the temperature of the mesosphere is extremely low, a persons blood would boil at normal body temperature.

``````-->  a) true

b) false
``````

the highest temperature in the mesosphere is at the top, which is -90oc.

``````a) true

-->  b) false
``````

what is the heat source for the mesosphere?

``````a) the troposphere

b) the sun

c) the mesosphere

-->  d) the stratosphere
``````

what type of clouds can be found in the mesosphere?

``````a) nimbus

b) cumulous

-->  c) noctilucent

d) stratus
``````

why would an astronaut without a spacesuit get severe ultraviolet burns in the mesosphere (besides having a lot of other problems)?

``````-->  a) the protective ozone layer is below her.

b) the sun is hotter there.

c) her blood would be boiling.

d) a & b
``````

the __ layer is above the mesosphere and the __ is below.

``````a) stratosphere, troposphere

-->  b) thermosphere, stratosphere

c) thermosphere, troposphere

d) troposphere, thermosphere
``````

the density of the mesosphere is very low because

``````-->  a) only 0.1% of the mass of the atmosphere is in or above the mesosphere.

b) the mesosphere is very cold.

c) the air pressure is very high.

d) ultraviolet radiation mixes up the gases.
``````

## diagram questions

No diagram questions associated with this lesson