Instrument Overview
  ===================
  The Lunar Prospector Magnetometer and Electron Reflectometer (MAGER)
  instruments are based on the instruments flown on the Mars Global
  Surveyor spacecraft [ACUNAETAL1992].  Some changes were made to the
  Lunar Prospector versions to account for the spinning spacecraft.
  Also, there is only one magnetometer sensor on Lunar Prospector.  The
  instrumentation consists of a 3-axis fluxgate magnetometer, a
  symmetric hemispherical electrostatic analyzer, and their common
  electronics box. The magnetometer (MAG) sensor is a wide-range (up to
  +/- 65,536 nT), low noise (6 pT RMS), high sensitivity (as low as +/-
  2 pT), triaxial fluxgate magnetometer.  The MAG sensor is an 11 x 6.5
  x 9 cm box.  The electron reflectometer (ER) has a 360 degree
  disk-shaped field-of-view. The electrostatic optics select energy and
  focus the particles onto an imaging detector.  The ER sensor is a 12
  cm diameter cylinder, 9 cm high.
 
  The combined mass of the Magnetometer and Electron Reflectometer is
  about 5 kg, and the two instruments use about 4.5 w of power.
 
 
  Science Objectives
  ==================
  The MAG/ER experiment will investigate the origin and nature of lunar
  crustal magnetic fields and constrain the size of a metallic core.
  The experiment will also provide global maps of the lunar crustal
  magnetic fields and provide estimates of the lunar induced magnetic
  dipole moment [BINDERETAL1998].
 
 
  Platform Mounting Descriptions
  ==============================
  The MAG sensor is mounted at the end of the MAG/ER boom about 2.6 m
  away from the spacecraft bus.  The ER and electronics box are mounted
  at the ends of a small cross bar, about 1 m inboard from the MAG. The
  ER unit is mounted so that its field-of-view includes the spin axis
  and is perpendicular to the boom.  The only blockage of the ER
  field-of-view is the boom itself.
 
 
  Operational Considerations
  ==========================
  The MAG sensor uses a combination of thermal blanketing and heaters
  to maintain its operating temperature.  The ER unit maintains its
  temperature using thermal blanketing, surface finishes, and its
  internal power dissipation.
 
  The magnetic fields measured by the MAG will be a combination of the
  Earth's magnetic field, the field carried from the Sun by the solar
  wind, and the Moon's field, which is extremely weak.  The magnetic
  field at the lunar surface is also affected by local deposits of
  magnetic material.
 
  The ER can measure magnetic fields as weak as one-millionth of the
  strength of the Earth's magnetic field.
 
 
  Operation and Sampling Modes
  ============================
  The magnetometer data are sampled 16 times a second, synchronous with
  the telemetry clock.  Data are compressed by delta-modulation to
  6-bits per axis per channel.  Occasional full samples (12 bits per
  axis plus range) are collected.
 
 
  Principal Investigator
  ======================
  The Co-I and magnetics group leader for the Lunar Prospector
  Magnetometer and Electron Reflector experiment is Dr. Robert Lin of
  the University of California, Berkeley.