Final answer:
The three primary features to look for in an exposure system are a telescope, instrument, and detector.
Step-by-step explanation:
The three primary features to look for in an exposure system are:
1. Telescope: It serves as a 'bucket' for collecting visible light or radiation at other wavelengths. Larger telescopes gather more light than the human eye can.
2. Instrument: Attached to the telescope, it sorts the incoming radiation by wavelength. It can separate different colors of light or identify spectral lines to determine an object's composition.
3. Detector: This device senses the radiation in the chosen wavelength regions and permanently records the observations made by the system.
The three primary features to look for in an exposure system used for measuring astronomical sources are telescopes, instruments for sorting radiation, and detectors. Telescopes act as large collectors of light, capable of capturing more radiation than the human eye. They are akin to a bucket that gathers rainwater, in that a larger telescope, much like a larger bucket, can collect more. Instruments attached to the telescope are responsible for sorting the incoming radiation by wavelength. This can range from a simple separation of blue and red light to viewing individual spectral lines that provide insights into the composition or movement of celestial objects. Finally, detectors sense the selected radiation and create a permanent record of the observations, which is crucial for later analysis and study.