There are two common ways to study deep space. These are with space exploration satellites or astronomy satellites. The space exploration satellites are also known as space probes. They leave Earth's orbit and travel out into deep space. They take pictures and they obtain detailed data of their research target and send those results back to Earth. Astronomy satellites, on the other hand, remain in Earth orbit, and simply use telescopes to study phenomena out in space.
Of course, space exploration satellites must be more durable than astronomy satellites because it takes them a very long time to get to their destinations. Space exploration satellites, however, can get very close to a planet and take very detailed photographs, whereas an astronomy satellite can see very far away, using a very powerful telescope, but the images that it obtains are usually not detailed at all.
Click here to see a picture obtained by a space exploration satellite.
Click here to see a picture obtained by an astronomy satellite.
All an astronomy satellite can do is take photographs, but a space exploration satellite can take physical measurements, send little probes into the planet to probe under layers of cloud cover and gases. They can take measurements like temperature, composition, and density.