With STIS, astronomers can observe a galaxy or nebula and gather spectral data from 512 different locations simultaneously. This means that many regions in a planet's atmosphere or many stars within a galaxy can be recorded in one exposure. Previous spectrographs had to make several observations of a target to collect the same information. STIS also has a camera that not only shows what an object looks like but how fast it is moving. From this information, scientists also can tell the direction in which an object is moving.
Scientists have a plan.
STIS will gather evidence for the existence of these exotic objects by looking at the behavior of gas and stars at the centers of galaxies, which many scientists believe harbor massive black holes. Objects that get sucked into black holes speed up as they whirl into the event horizon and get tossed around. These objects also are very hot. STIS will measure the temperatures and velocities of these objects. To really determine the velocities at which stars and gas orbit around the center of these exotic objects, scientists must take measurements at no fewer than 10 different locations.