New Approaches and Instrumentation for in-situ Exploration of the Upper Atmosphere

Abstract:

Two new concepts for exploring the upper atmosphere are presented and discussed. The first concept focuses on measuring atmospheric parameters in-situ from a spaceborne platform. It consists of an instrument that utilizes both established and new methods for measuring density, winds, temperature, and composition of the atmospheric gas. A previously-developed ionization-gauge based pressure sensor is used to measure density, and composition is measured by a newly-developed mass spectrograph capable of high readout rates. Temperature and cross-track winds are measured using the established scanning-baffle technique , but a second newly-conceived method based on an imaging sensor is also included. In-track winds are measured with a time-of-flight approach that employs a high-speed mechanical modulation device. The operational principles of these sensors are discussed in detail, development status discussed, and current testing results presented.

The second concept utilizes spaceborne lidar to measure altitude profiles of atmospheric density, winds, and temperature in the altitude range 80-600 km. At the heart of the system is a laser transmitter/receiver pair that is sensitive to atomic oxygen. The concept is currently under study, and several paradigms for potential deployment and operation are presented. A concept for the ultraviolet laser system used for the atomic oxygen measurements is also under development, and the status of that development is also reported upon.