Question

Satellites designed to observe the radiation from cold (3 K) dark space have sensors that are shaded from the Sun, Earth, and the Moon and are cooled to very low temperatures. Why must the sensors be at low temperature?

(a) To reduce conduction
(b) To reduce radiation
(c) To minimize heat transfer from the surroundings
(d) To maximize convection

Answer 1

Satellite sensors must be at low temperatures to reduce radiation noise and minimize heat transfer from the satellite, allowing detection of very faint signals from cold dark space.

The Correct Option is; c) To minimize heat transfer from the surroundings

Step-by-step explanation:

Satellites designed to observe the radiation from the cold (3 K) dark space must have sensors at very low temperatures to prevent their own thermal radiation from interfering with the observations.

Since warm objects emit infrared energy, cooling the sensors is necessary to reduce radiation noise, which can obscure the faint signals from the depths of space.

This is achieved by isolating the detector in very cold surroundings, often near absolute zero, with the use of liquid helium, to minimize the heat transfer from the satellite to the sensors.

The sensors of satellites designed to observe the radiation from cold (3 K) dark space must be at low temperature for several reasons.

First, by cooling the sensors to very low temperatures, it reduces conduction of heat from the surroundings. Second, it helps to minimize heat transfer from the surroundings.

Lastly, low temperatures also help to reduce radiation emitted by the telescope structure and optics, preventing heat from reaching the infrared detector.