An all-fiber coherent laser radar system capable of high-resolution range and line of sight velocity measurements is under development with a goal to aid NASA's new Space Exploration initiative for manned and robotic missions to the Moon and Mars. Precision range and velocity data are key parameters to navigating planetary landing pods to the pre-selected site and achieving autonomous safe soft-landing. By employing a combination of optical heterodyne and linear frequency modulation techniques [1-3] and utilizing state-of-the-art fiber optic technologies, highly efficient, compact and reliable laser radar suitable for operation in a space environment is being developed.The all-fiber coherent laser radar has several important advantages over more conventional pulsed laser altimeters or range finders. One of the advantages of the coherent laser radar is its ability to directly measure the platform velocity by extracting the Doppler shift generated by the platform motion. The Doppler velocity measurement is about two orders of magnitude more accurate than the velocity estimates obtained by laser altimeters using the rate of change in range [4]. Another advantage is continuous-wave operation that allows the use of highly efficient and reliable commercial off-the-shelf fiber optic telecommunication components. This paper will describe the design and operation of this laser radar sensor and discuss its projected performance. A laboratory breadboard system has already been developed as a step toward a flight prototype. The experimental data representing the potentials of this laser radar system will be reported.

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SABER (Sounding of the Atmosphere using Broadband Emission Radiometry) is a 10-channel infrared radiometer that is one of four instruments on the NASA TIMED (Thermosphere-Ionosphere-Mesosphere Energetics and Dynamics) satellite mission to study the structure, energetics, chemistry, and dynamics of the Earth’s mesosphere and lower thermosphere. The TIMED spacecraft was launched into a 625 km circular polar orbit (74.1º inclination) via a Boeing Delta II rocket from Vandenberg Air Force Base on 7 December 2001. SABER continues to operate nominally and collect data routinely as it has for over 21 years. Over 2,200 peer-reviewed journal articles have been published worldwide using SABER data. A list of these articles is included in the Supporting Information accompanying this paper. The Space Dynamics Laboratory (SDL) of Utah State University designed, fabricated, and calibrated the SABER instrument in close collaboration with NASA Langley Research Center, Hampton University, and Global Atmospheric Technologies and Science (GATS). This paper provides a detailed technical description of the SABER instrument, including performance specifications and observed instrument performance.

The findings of an independent panel commissioned by NASA's Earth Science Enterprise (ESE) to assess the current missions utilizing advanced solid-state lasers and the programmatic actions by the Enterprise to define how NASA Centers will cooperate on future lidar competitive opportunities together formulate a strategy for technology development of advanced solid-state laser systems.In this paper we will describe a program created to address risks in the development of laser transmitter technologies. This program grew out of concern that there are no lasers as active sources for space-based remote sensing that have been space qualified for long-term science measurements. Presently, the risks inherent in developing these technologies have been born by programs funded to produce scientific results. The intention of this program is to mitigate risks in certain technical areas so that other technology programs can further the maturation of the instruments prior to infusion into a science program. The program will invest in several critical areas:• Advancing transmitter technologies to enable science measurements (tropospheric ozone, water vapor, winds, altimetry) • Development and qualification of space-based laser diode arrays • Advancing nonlinear wavelength conversion technology for space-based lidars

Future remote sensing instruments for the National Aeronautic and Space Administration (NASA) Earth Science Enterprise (ESE) will depend heavily upon lidars as active sources. Applications will include measurement of the chemical composition of the atmosphere, including global atmospheric CO 2 , tropospheric wind velocity and surface altimetry. In many cases, the technology requirements for these measurements exceed the state of the art in commercially available laser systems. Consequently, considerable research will be necessary in laser technologies in order to enable the future measurement needs of the ESE.In this paper we will describe the strategy that NASA's ESE will use to develop the necessary laser and supporting technologies. We will illustrate roadmaps of the various measurement needs detailing specific technology investments. In particular we will review the findings from workshops recently conducted by NASA to determine the technology drivers for these measurements.The Earth Science Technology Office is responsible for developing advanced technologies for the ESE, as such, this information is presented in order to communicate the relevancy of, and the need for investments in these technologies to the broadest technical audience.