HST: How do Scientists point the telescope in the right direction?

How do Scientists point the telescope in the right direction?
	Where are we now? Gyroscopes are an important part of Hubble's Pointing Control System. Gyroscopes are like motion detectors. As the HST moves, the gyros can sense its movement and send information back to the flight computer about HST's exact position. With moment-to-moment updates from the gyroscopes, the computer always knows how far the Hubble has moved. When Hubble has moved far enough, the computer slows down the spinning Reaction Wheels, and the telescope coasts into place.