NASA has more than 20 Earth-observing satellites that provide researchers a global point of view on the interconnected Earth system. Like musical instruments in an orchestra, the specific satellite instruments require to be “in tune” with each other in order for scientists to get the most out of their data.
This electro-magnetic spectrum demonstrates how energy travels in waves; Humans can just see noticeable light, however the entire spectrum is used by NASA instruments to observe Earth and more. Credit: NASA
Thats where air-LUSI is available in. Established in partnership with the National Institute of Standards and Technology (NIST), U.S. Geological Survey and McMaster University, air-LUSI is a telescope that determines how much light is shown off the lunar surface area to evaluate the quantity of energy Earth-observing satellites receive from moonlight. It was installed aboard the ER-2 airplane managed by and flying out of NASAs Armstrong Flight Research Center in Palmdale, California. The ER-2 is a high-altitude aircraft that flew at 70,000 feet, above 95% of the atmosphere, which can spread or absorb the reflected sunshine. This permitted air-LUSI to gather really accurate, NIST traceable measurements that are comparable to those a satellite would make from orbit. In order to enhance the accuracy of lunar reflectance models, air-LUSI measurements are precise with less than 1% unpredictability. Throughout the March flights, air-LUSI measured the Moon for four nights prior to a complete Moon.
This airborne technique has the benefit of studying moonlight during different phases of the Moon while being able to bring the instrument back between flights for examination, upkeep, and, if necessary, repair.
Shown is the air-LUSI telescope placed to measure a simulated Moon in a lab for testing and calibration prior to and after the flight campaign. Credit: Kevin Turpie
Making Improvements for Better Accuracy
Light gathered by a telescope gets in an integrating sphere which directs the light to the spectrometer, which is an instrument that determines variations of light waves. Considering that then, the air-LUSI team has actually continued to enhance the instruments accuracy.
The team improved the internal screen so they can better inspect instrument precision over a higher variety of wavelengths, from the ultraviolet to the near infrared. They were also able to upgrade the integrating sphere to eliminate little effects of changing temperature.
” This will help the instrument make measurements with the more than 99% accuracy levels were searching for,” stated Turpie.
Making these modifications was challenging. Hold-ups from the COVID-19 pandemic caused the primary engineer, who was working on the instrument updates and repairs, to develop a new remote work strategy. Both he and the principal detective received unique approval to have parts delivered directly to their homes so they could work on the instrument and be gotten ready for the 2022 flights.
Utilizing the Moon as a Common Standard
The data from 2019 and 2022 together has the possible to assist researchers in making Earth-observing satellite information in the ultraviolet to near-infrared variety more constant. In addition, the typical Moon requirement would make it much easier to compare and tweak future and existing satellite observations. NASAs upcoming Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission is intending on using the Moon as a common benchmark to make its observations more inter-consistent and precise with other satellite measurements of Earth. Over the next years, PACE and the future orbiting sensors of NASAs Earth System Observatory will assist produce a more cohesive photo of our planet.
” Having a common calibration source beyond the Earth will help us reach this objective,” stated Turpie. “Once air-LUSI measurements are used to improve the precision of the total amount of light coming from the Moon, we can take extensively more accurate measurements of Earth using current and future space-borne observatories.”
NASAs ER-2 airplane revealed prepared for fueling and flight preparations. Credit: Ken Ulrich
NASAs air-borne Lunar Spectral Irradiance, or air-LUSI, flew aboard NASAs ER-2 aircraft from March 12 to 16 to accurately determine the quantity of light shown off the Moon. Shown moonlight is a stable source of light that researchers are making the most of to improve the accuracy and consistency of measurements among Earth-observing satellites.
” The Moon is exceptionally stable and not affected by factors in the world like environment to any large degree. It becomes a great calibration recommendation, an independent benchmark, by which we can set our instruments and see whats occurring with our world,” said air-LUSIs primary detective, Kevin Turpie, a research study professor at the University of Maryland, College Park.
The air-LUSI flights belong to NASAs thorough satellite calibration and recognition efforts. The results will compliment ground-based websites such as Railroad Valley Playa in Nevada, and together will provide orbiting satellites with a robust calibration dataset.
NASA has more than 20 Earth-observing satellites that offer researchers a global point of view on the interconnected Earth system. Like musical instruments in an orchestra, the individual satellite instruments require to be “in tune” with each other in order for scientists to get the most out of their data. It was mounted aboard the ER-2 aircraft managed by and flying out of NASAs Armstrong Flight Research Center in Palmdale, California. Light collected by a telescope enters an incorporating sphere which directs the light to the spectrometer, which is an instrument that measures variations of light waves. NASAs upcoming Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) objective is preparing on utilizing the Moon as a typical standard to make its observations more precise and inter-consistent with other satellite measurements of Earth.