Unit C Section 2 Introduction Thermal Energy Transfers in Different Ways
Completion requirements
Section 2: Thermal energy transfers in different ways.
Unit C: Section 2 – Introduction
Figure C.S.2.1 – When a spaceship moves in and out of Earth’s atmosphere, it generates a lot of heat.
Figure C.S.2.2 – Heat resistant tiles prevent spacecraft from lighting on fire.
Spacecraft Heat Tiles
When space shuttles return to Earth, they fall through Earth’s atmosphere at speeds of about 28 000 km/h. This is about 30 times faster than the speed of an average airplane.
At this high speed, friction produces huge amounts of heat around the spacecraft. Friction is caused by many particles of air rubbing quickly against the outside of the space shuttle. It produces enough heat energy to raise the temperature around the space shuttle to 1500o C. That is hot enough to melt iron.
To protect astronauts from high heat during re-entry, space shuttles are covered in special ceramic tiles that conduct heat poorly. They are good insulators. The tiles keep the inside of the space shuttle cool even when the outside surface temperature is extremely hot.
When space shuttles return to Earth, they fall through Earth’s atmosphere at speeds of about 28 000 km/h. This is about 30 times faster than the speed of an average airplane.
At this high speed, friction produces huge amounts of heat around the spacecraft. Friction is caused by many particles of air rubbing quickly against the outside of the space shuttle. It produces enough heat energy to raise the temperature around the space shuttle to 1500o C. That is hot enough to melt iron.
To protect astronauts from high heat during re-entry, space shuttles are covered in special ceramic tiles that conduct heat poorly. They are good insulators. The tiles keep the inside of the space shuttle cool even when the outside surface temperature is extremely hot.
Figure C.S.2.3 – Space shuttles are covered in special heat resistant tiles.
Watch More
Spacecraft Heat Shields
Watch this video to learn more about why spacecraft need heat shields. Space scientists are developing some new types of heat shields, such as fabric that can resist up to 3000°C.
Watch this video to learn more about why spacecraft need heat shields. Space scientists are developing some new types of heat shields, such as fabric that can resist up to 3000°C.
Space Shuttle Heat Tiles
This video explains how space shuttle heat tiles are made from a very common substance on Earth.
This video explains how space shuttle heat tiles are made from a very common substance on Earth.
Words to Think About:
Check out the word cloud below. It pictures the important words that you are going to learn in this section. Watch for these words, and combinations of these words, as you read. When you see them highlighted, you can click on them to learn more about
what the word means.
You can also visit the course glossary and read definitions for all of these words.
Lessons in This Section
Lesson C5: Heat Transfer: Conduction
Key Question – Ouch! Why do you get burned when you touch something hot?
Lesson C6: Heat Transfer: ConvectionKey Question – How do you heat an entire house with only one furnace?
Lesson C7: Heat Transfer: RadiationKey Question – How does heat travel to us through space from the Sun?
Reading and Materials for This Section
Science in Action 7
Reading Pages: 209–221
Materials Lists for Unit:
Figure C.S.2.4 – Spacesuits contain machines that help maintain a comfortable temperature for the astronaut.
Figure C.S.2.5 – Controlling heat energy is important for astronauts on spacewalks.
Protective Spacesuits
In a way, to talk about the “temperature” of space in the same way we measure temperature on Earth is very misleading. Space is basically empty. Almost no particles of matter occur in space, and the particles in space are spread very far apart—so far apart that measuring their average energy is impossible. One could say that space does not have high temperature or low temperature; rather, it has NO temperature at all.
Because the temperature of space cannot be measured, scientists use advanced methods to estimate the temperature of space, and they have found that it is very cold—just above absolute zero. But putting objects into space changes everything. Objects in space, such as astronauts in spacesuits, are heated by the Sun, and objects in space cannot transfer the heat energy they gain to nearby particles because no particles are nearby. This means objects in space can have wild temperature swings!
In space, when the Sun shines directly on an object, it can become extremely hot quickly. In shadowed places away from the Sun, the temperature of an object can drop quickly to -100o C. Astronauts who go on spacewalks need special spacesuits to deal with these temperature extremes so that their bodies are comfortable.
Bulky spacesuits have many layers that act as insulation from sudden temperature extremes. Spacesuits are white to keep astronauts cooler by reflecting heat from the Sun. Astronauts generate their own body heat, too. This can be uncomfortable when trapped in a spacesuit. For this reason, spacesuits contain a water tube cooling system.
Figure C.S.2.6 – This spacesuit was made specifically for Chris Hadfield, a Canadian astronaut.
Watch More
Spacesuit Layers
Watch this video to learn more about the materials that make up the layers in spacesuits.
Watch this video to learn more about the materials that make up the layers in spacesuits.
Putting on a Spacesuit
This video shows the process of putting on a spacesuit. Getting dressed is a real chore!
This video shows the process of putting on a spacesuit. Getting dressed is a real chore!