Spacecraft are complex, technological objects that have to function far from Earth in the harsh environment of space. They collect science data and send it to Earth. But, as strange as they appear to be, it can help to understand them if we compare spacecraft to ourselves!
Think of the spacecraft as a living organism. As a lesson, this can be done in either of two directions. If the students are familiar with spacecraft they can be prompted with body parts and attempt to identify the analogous spacecraft part.
This will work well if the students have a high quality picture of a modern spacecraft. Pictures of planetary spacecraft work the best since they have the least amount of their equipment hidden or encased in the body of the spacecraft.
In the other direction, the students can be prompted with spacecraft parts and challenged to identify the relative anatomical part. This can lead to interesting discussions and differences of opinion ('Is electrical wiring more like blood vessels or nerves?').
The list below is not exhaustive but it sets the stage for a good follow-on activity. Identify a mission and a destination for a spacecraft and have teams of students design the spacecraft. They must be sure that the spacecraft has all the correct parts to fulfill critical functions. (It cannot have solar panels if it is going to Neptune, but it can have radioisotope thermoelectric generators (RTGs) if it is going to Mercury; however, including both takes up critical weight).
Keep in mind, landers and "rovers" are spacecraft too. Rovers require ways to move and navigate.
We human beings are built, and have to do certain things, to remain alive. The same is true for spacecraft.
Humans: Food/Water Spacecraft: Solar panels (sunlight), radioisotope thermoelectric generators (heat from the decay of radioactive material; necessary in the weak lighting far from the Sun), or batteries (stored energy) Humans: Body/Torso Spacecraft: "Bus" (The housing that holds the spacecraft components and to which other devices are attached) Humans: Brain Spacecraft: Computer(s) Humans: Nerves Spacecraft: Electrical wiring Humans: Skin Spacecraft: Blankets (for temperature control [the spacecraft can not sweat but it can have radiators or louvers to get rid of excess heat] and meteorite protection) Humans: Legs Spacecraft: Rocket motors, fuel tanks (Because objects in motion tend to remain in motion, most spacecraft do not need to constantly burn fuel to move; their small rockets [thrusters] are used to change their orientation in space; a small amount of fuel lasts many years) Humans: Blood vessels Spacecraft: Fuel lines Humans: Arms Spacecraft: Booms
Spacecraft also have sense organs to explore the places that they visit. They must communicate the data back to Earth and receive new instructions.
Humans: Eyes (sense organs) Spacecraft: Camera(s), spectrometers, magnetometers, other science instruments Humans: Neck Spacecraft: Scan platform (which pivots around so that the instruments can point in the desired direction without reorienting the whole spacecraft) Humans: Ears/mouth Spacecraft: Communications antenna(e) (and receivers and transmitters)
Can you think of any other comparisons?
Lesson Plans and Activities