Flown on NASA’s ER-2 aircraft, a high-altitude aircraft based at NASA Armstrong Flight Research Center in Edwards, California
The Airborne Lunar Spectral Irradiance (air-LUSI) instrument will help characterize the Moon as a reference standard for calibrating Earth-observing satellites. These measurements will inform models of the lunar irradiance that predict how much light a space-based sensor will receive when it observes the Moon. This allows calibration of the sensor on-orbit without the need for additional calibration hardware. This is of particular interest to small satellites and cubesats that lack the payload space for onboard calibration instruments.
Primary developer of Air-LUSI instrument, which includes a telescope and spectrograph, and responsible for calibration. The automatic pointing system to lock the telescope on the Moon was developed by McMaster University.
Air-LUSI has completed seven engineering and demonstration ER-2 flights, successfully recording lunar observations on six flights. Its first science flights were conducted in March of 2022 with the instrument flying and making successful measurements on four of five scheduled nights. A second science campaign is scheduled for March 2025.
The “near-space airplane” operates as high as 21 kilometers (about 13 miles) above sea level, to enable measurements above most of Earth’s interfering atmosphere. Air-LUSI flies at night to observe the Moon with the telescope mounted inside a wing pod that is open to air that can be as cold as minus 60 degrees Celsius. A robotic mount keeps the telescope tracking the Moon, compensating for aircraft motion.
NIST, University of Maryland Baltimore County, NASA Headquarters, NASA Goddard, University of Guelph, McMaster University and the U.S. Geological Survey
NIST, University of Maryland Baltimore County, NASA Goddard, NASA Armstrong, McMaster University and the U.S. Geological Survey