Click on the graphic to find out more about the various pieces. This cone-shaped beak can send data back to Earth at a rate of 3,600 bits per second. Commands from Earth trickle in at 250 bits per second. Compare that to the 56,000 bits per second that the fastest computer modems can toss back and forth these days. Gamma Ray Spectrometer Gamma rays are high-energy particles of light.
Some radioactive elements emit gamma rays as a matter of course.
Other elements emit gamma arrays as they are bombarded by cosmic rays. These two instruments will measure the magnetic field, which will be primarily the Earth's magnetic field, plus that generated by the solar wind, plus a tiny, tiny bit from the moon itself. That's not even enough to light up the 400-watt halogen lamp in your living room. As its name indicates, the neutron spectrometer detects particles known as neutrons. Scientists will be looking for slow-moving neutrons that have lost much of their energy by bouncing off a hydrogen atom.