The 24 Million Kilometer Optical Link with the Mercury Laser Altimeter

A recent experiment has been completed at NASA Goddard Geophysical and Astronomical Observatory (GGAO) where an optical link has been achieved with the Mercury laser altimeter (MLA) instrument about the Messenger spacecraft on its way to Mercury. A pulsed laser source at 1 micron based on Earth has been recorded on MLA. Simultaneously, the spacecrafts altimeter has been properly aimed and laser pulses transmitted to earth where they were detected and recorded at the same facility. This optical link was used to calibrate and verify operation of the MLA instrument and onboard laser, as well as to gain valuable information with the methods and means of very long range optical communication pointing and receiving techniques. An overview of this experiment, the hardware, and data products will be presented.