Step 1: Know the two sensor families.
Remote sensing sensors are grouped into photographic sensors, which use film cameras, and non-photographic sensors, which use electronic detectors that record energy as digital signals.
Step 2: Think about working from space.
A satellite stays in orbit for years and cannot easily carry, change or return rolls of film.
Step 3: Rule out photographic sensors.
Because film handling is impractical in orbit, photographic (film) sensors are not suited to satellites.
Step 4: Consider the narrow UV and infrared options.
UV-only or infrared-only sensors describe just one band; they are not the general type used for satellite imaging.
Step 5: Match the right type.
Satellites use electronic scanners that send their readings down as digital data, which are non-photographic sensors.
Step 6: State the answer.
The sensor used is a non-photographic sensor.
\[ \boxed{\text{Non-photographic sensor}} \]