Objectives:

1. Determination of a Global, Geodetically Referenced 0.2 degree x 0.2 degree Topographic Grid of Mars to a Vertical Accuracy Better than 30 m Suitable for Addressing Problems in Geology, Geophysics and Atmospheric Circulation
2. Acquisition of Globally Distributed Topographic Profiles of the Martian Surface on Short Baselines (~100 km) with a vertical precision of ~ 2 meters Suitable for Addressing a Range of Problems in Local and Regional Scale Geology
3. Determination of a Global 0.2 degree x 0.2 degree Grid of 1.06 micron Surface Reflectivity of Mars to a Precision of ~10% Suitable for Contributing to Analysis of Global Surface Mineralogy and Polar Cap Variation

Instrumentation:

A diode-pumped 1.06 micron Nd:YAG laser transmitter and a 50 cm diameter parabolic receiver provides 160 meter diameter horizontal resolution and 2 meter vertical precision at 10 pulses per second.

Measurements:

• Altimetry: Measures Spacecraft to Surface Distance
• Resolution:
• Vertical: 2 m (local) 30 m (global)
• Horizontal: 160 m
• Laser Transmitter:
• Diode Pumped, Q-Switched Nd:YAG laser
• Pulse Energy: 40-45 mJ
• Repetition Rate: 10 pulses/sec continuous
• Beam Diameter: 1cm
• Beam Divergence: 0.45 mrad
• Antenna Receiver: 50 cm Parabolic Antenna
• Si APD Detector
• 4 Electronic Filters (20, 60, 180 and 540 ns)
• Electronics:
• 80C86 microprocessor, 54 HC Family Logic
• Data Rate: 618 bits/sec