In this paper we present the final configuration of the space flight laser transmitter as delivered to the Lunar Orbiter
Laser Altimeter (LOLA) instrument along with some in-space operation performance data. The LOLA instrument is
designed to map the lunar surface and provide unprecedented data products in anticipation of future manned flight
missions. The laser transmitter has been operating on orbit at the Moon continuously since July 2009 and accumulated
over 1.8 billion laser shots in space. The LOLA laser transmitter design has heritage dated back to the MOLA laser
transmitter launched more than 10 years ago and incorporates lessons learned from previous laser altimeter missions at
NASA Goddard Space Flight Center.
A compact, passively q-switched, single mode laser has been developed for space based lidar applications. The
Nd:YAG laser produces 50mJ pulse-energy at 100 Hz repetition rate in a near diffraction limited beam with more than
99.99% of the pulses in a single longitudinal mode. This laser was initially developed as a candidate for the ICESat-2
mission, which requires five years continuous operation in space. The laser is based on two newly developed
technologies, Etalon Coupled High Output (ECHO) oscillator and Ring Amplified Solid State Laser (RASSL). In this
paper, we will present the laser design and discuss the laser performance and experimental results. We will also present
a unique laser package concept.
The first NASA Ice, Cloud and land Elevation Satellite (ICESat) was launched in January 2003 and placed into a nearpolar
orbit whose primary mission was the global monitoring of the Earth's ice sheet mass balance. ICESat has
accumulated over 1.8 B shots in space and provided a valuable dataset in the study of ice sheet dynamics over the past
few years. NASA is planning a follow-on mission ICESat-2 to be launched tentatively in 2015. In this paper we will
discuss the development effort of the laser transmitters for the ICESat-2 mission.
The Lunar Orbiter Laser Altimeter (LOLA) is one of seven instruments aboard the Lunar
Reconnaissance Orbiter (LRO) spacecraft with the objectives to determine the global
topography of the lunar surface at high resolution, measure landing site slopes and search
for polar ices in shadowed regions. The LOLA laser transmitter is a passively Q-switched
crossed-Porro resonator. All components used in the laser have space flight heritage. The
flight laser bench houses two oscillators (a primary and a cold spare) that are designed to
operate sequentially during the mission. If the primary laser can no longer provide
adequate scientific data products, the secondary laser will be turned on. The baseline
mission calls for LOLA (and LRO) to spend about one year studying the Moon. Since
LOLA operates at 28 Hz, the laser system needs to produce approximately one billion
pulses during the primary one year mission. To validate that the LOLA laser design is
capable of meeting this requirement, the LOLA Engineering Model (EM) laser has been
subjected to extended operation testing in vacuum. In this paper we will summarize the
longevity validation test effort of the LOLA EM laser.
NASA Goddard Space Flight Center (GSFC) has been engaging in Earth and planetary science instruments development
for many years. With stunning topographic details of the Mars surface to Earth's surface maps and ice sheets dynamics
of recent years, NASA GSFC has provided vast amount of scientific data products that gave detailed insights into
Earth's and planetary sciences. In this paper we will review the past and present of space-qualified laser programs at
GSFC and offer insights into future laser based science instrumentations.
We present the final configuration of the space flight laser transmitter as delivered to the LOLA instrument. The laser
consists of two oscillators with co-aligned outputs on a single bench, each capable of providing one billion plus shots.