PATHWAYS TO ANSWERS: THE SCIENTIFIC PROCESS IN ACTION
ANGLE ON COOLING
EFFECT OF DISTANCE AND INCLINATION
1-2 45-minute periods
this lesson, students discuss what heat is and how it travels.
They discover that one way to cool an object in the presence
of a heat source is to increase the distance from it or change
the angle at which it is faced. The students perform an experiment
that measures how the heat experienced by a test subject changes
as the distance or the viewing angle changes. The students
learn to distinguish which effect is more important for determining
the seasons on Earth. They also learn how the MESSENGER mission
to Mercury takes advantage of these passive cooling methods
to keep the spacecraft comfortable in a high-temperature environment.
How do distance
and inclination affect the amount of heat received from a
spacecraft with its solar panels angled toward the Sun for safe
- Sunlight can be
felt as heat when it interacts with matter.
- The intensity of
light decreases as the distance from the light source increases.
- The angle at which
a light source is viewed affects the intensity of light to which
the object is exposed and therefore the amount of heat generated
in the object.
- Seasons on Earth
are caused by the tilt of the Earth's rotational axis.
Because Mercury is much
closer to the Sun than the Earth, it is exposed to much more sunlight
than objects on the surface of Earth. The MESSENGER mission designers
have had to come up with a variety of ways to keep the spacecraft
cool in the hot Mercurian environment. Two cooling methods are keeping
the distance from the sunlit areas of Mercury’s surface large
enough to limit the amount of infrared radiation received from the
surface and making sure the solar panels do not view the Sun face-on.