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Temperature SystemHow does DS1 control its temperature? |
There are a variety of thermal control devices on DS1. They include:
All of these devices work together to create a delicate thermal balance for the entire spacecraft. Some monitor heat, some work to keep certain parts warm, and others are cooling devices.
Heating is controlled both actively and passively on DS1. Active heat control means that a device is turned off or on to change the temperature. An example of an active heat control device on Earth would be an air conditioner or heater. Passive heat control happens when a device can help control heat without being turned on or using any power. When you put on a sweater, you are using a passive heat control device.
MLI blankets passively insulate the spacecraft while minimizing any heat absorption from the Sun. They are made of thin, radiating top layers of aluminized Kapton (a thin plastic also with high reflectivity). In addition, DS1 has active heaters; some work automatically, using sensors to detect when the heaters should be turned on or off. Other heaters are controlled by command. For example, heaters can be turned on when subsystems that naturally produce heat are turned off.
There are no active cooling devices on DS1. Cooling is accomplished primarily by passive radiators, and also by not exposing certain spacecraft surfaces/subsystems to the Sun. There are radiators (for passive cooling) around the heat emitting subsystems. The radiators cool the spacecraft because radiation moves heat from a warm area to the coldest area near it, which in this case is toward space.
In addition to these devices, most spacecraft are designed and built with sides intended to point toward the Sun and sides intended for shade. Instruments that must be kept warm or cold will be placed accordingly.
What could go wrong on DS1 if it gets too hot?
What is attitude control?
