NASA will quickly launch a one-of-a-kind instrument, known as Arcstone, to enhance the standard of knowledge from Earth-viewing sensors in orbit. On this know-how demonstration, the mission will measure daylight mirrored from the Moon— a way known as lunar calibration. Such measurements of lunar spectral reflectance can in the end be used to set a high-accuracy, common customary to be used throughout the worldwide scientific neighborhood and industrial area trade.
To make sure satellite tv for pc and airborne sensors are working correctly, researchers calibrate them by evaluating the sensor measurements in opposition to a identified customary measurement. Arcstone would be the first mission completely devoted to measuring lunar reflectance from area as a technique to calibrate and enhance science knowledge collected by Earth-viewing, in-orbit devices.
“Probably the most difficult duties in distant sensing from area is reaching required instrument calibration accuracy on-orbit,” mentioned Constantine Lukashin, principal investigator for the Arcstone mission and bodily scientist at NASA’s Langley Analysis Middle in Hampton, Virginia. “The Moon is a superb and accessible calibration supply past Earth’s ambiance. The sunshine mirrored off the Moon is extraordinarily secure and measurable at a really excessive degree of element. Arcstone’s objective is to enhance the accuracy of lunar calibration to extend the standard of spaceborne distant sensing knowledge merchandise for generations to come back.”
Throughout its deliberate six-month mission, Arcstone will use a spectrometer — a scientific instrument that measures and analyzes mild by separating it into its constituent wavelengths, or spectrum — to measure lunar spectral reflectance. Anticipated to launch in late June as a rideshare on a small CubeSat, Arcstone will start amassing knowledge, a milestone known as first mild, roughly three weeks after reaching orbit.
“The mission demonstrates a brand new, extra cost-efficient instrument design, {hardware} efficiency, operations, and knowledge processing to realize high-accuracy reference measurements of lunar spectral reflectance,” mentioned Lukashin.
Measurements of lunar reflectance taken from Earth’s floor could be affected by interference from the ambiance, which may complicate calibration efforts. Researchers already use the Solar and Moon to calibrate spaceborne devices, however not at a degree of precision and settlement that would come from having a common customary.
Lukashin and colleagues need to improve calibration accuracy by getting above the ambiance to measure mirrored photo voltaic wavelengths in a method that gives a secure and common calibration supply. One other latest NASA mission, known as the Airborne Lunar Spectral Irradiance mission additionally used sensors mounted on high-altitude plane to enhance lunar irradiance measurements from planes.
There’s not an internationally accepted customary (SI-traceable) calibration for lunar reflectance from area throughout the scientific neighborhood or the industrial area trade.
“Devoted radiometric characterization measurements of the Moon have by no means been acquired from a space-based platform,” mentioned Thomas Stone, co-investigator for Arcstone and scientist on the U.S. Geological Survey (USGS). “A high-accuracy, SI-traceable lunar calibration system permits a number of essential capabilities for space-based Earth observing missions similar to calibrating datasets in opposition to a typical reference – the Moon, calibrating sensors on-orbit, and the power to bridge gaps in previous datasets.”
If the preliminary Arcstone know-how demonstration is profitable, an extended Arcstone mission might permit scientists to make the Moon the popular reference customary for a lot of different satellites. The brand new calibration customary may be utilized retroactively to earlier Earth knowledge information to enhance their accuracy or fill in knowledge gaps for knowledge fields. It might additionally enhance high-precision sensor efficiency on-orbit, which is vital for calibrating devices that could be delicate to degradation or {hardware} breakdown over time in area.
“Earth observations from area play a vital function in monitoring the environmental well being of our planet,” mentioned Stone. “Lunar calibration is a strong and cost-effective technique to obtain excessive accuracy and inter-consistency of Earth commentary datasets, enabling extra correct assessments of Earth’s present state and extra dependable predictions of future traits.”
The Arcstone know-how demonstration undertaking is funded by NASA’s Earth Science Expertise Workplace’s In-space Validation of Earth Science Applied sciences. Arcstone is led by NASA’s Langley Analysis Middle in partnership with Colorado College Boulder’s Laboratory for Atmospheric and House Physics, USGS, NASA Goddard House Flight Middle in Greenbelt, Maryland, Resonon Inc., Blue Canyon Applied sciences, and Quartus Engineering.
For extra data on NASA’s Arcstone mission go to:
https://science.larc.nasa.gov/arcstone/about/
