Configurations of Magnetometers
Unlike ground based magnetometers that can be oriented by the user to determine the direction of magnetic field, in space the user is linked by telecommunications to a satellite traveling at 25,000 km per hour. The magnetometers used need to give an accurate reading quickly to be able to deduce magnetic fields. Several strategies can be employed, it is easier to rotate a space craft about its axis than to carry the weight of an additional magnetometer. Other strategy is to increase the size of the rocket, or make the magnetometer lighter and more effective. One of the problems, for example in studying planets with low magnetic fields like Venus, does require more sensitive equipment. The equipment has necessarily needed to evolve for today's modern task. Ironically satellites launched more the 20 years ago still have working magnetometers in places where it would take decades to reach today, at the same time the latest equipment is being used to analyze changes in the Earth here at home.
Read more about this topic: Spacecraft Magnetometer