NASA’s “CubeSat” will test miniaturized weather satellite technology


Behind every weather forecast, from your local five-day forecast to a belated hurricane track update, are the satellites that make it possible. Government agencies depend on observations from weather satellites to inform forecasting models that help us prepare for approaching storms and identify areas that need to be evacuated or emergency first responders.

Weather satellites have traditionally been large, both in the effort required to build them and in their actual size. They can take several years to build and can be as big as a small school bus. But all that could change in the future with the help of a shoebox-sized satellite that will start orbiting Earth later this month.

The NASA-funded CubeSat, called Microwave Radiometer Technology Acceleration (MiRaTA), will be launched into Earth orbit from the rocket carrying America’s next major weather satellite (NOAA’s JPSS-1) into space. MiRaTA is designed to demonstrate that a small satellite can carry instrument technology capable of reducing the cost and size of future weather satellites and has the potential to routinely collect reliable weather data.

Microwave radiometers are one of the most powerful instruments aboard weather satellites today. These sensitive instruments measure radiofrequency signals related to thermal radiation emitted by atmospheric gases, such as molecular oxygen and water vapor, and also detect particles such as cloud ice. These data are essential inputs for models that track storms and other weather events. Calibration of these radiometers is important to prevent them from drifting so that their data can be used for accurate weather and climate models. Therefore, a calibration target is usually included in the satellite to help the radiometer maintain its accuracy.

Miniaturizing microwave radiometer instruments to fit a CubeSat poses the challenge of finding a calibration instrument that is not only accurate but also compact, said Kerri Cahoy, Principal Investigator for MiRaTA and Associate Professor in the Department of Aeronautics and Astronautics from the Massachusetts Institute. of Technology. “You don’t have room for the bulky calibration targets that you would normally use on larger satellites,” Cahoy said. “Microwave radiometer calibration targets on larger satellites may be the size of a toaster, but for CubeSats they should be the size of a deck of cards.”

Cahoy and her colleague William Blackwell, manager of microwave radiometer instruments at MIT Lincoln Laboratory, found a solution based on a technique she studied in graduate school called radio occultation (RO), by which Radio signals received from GPS satellites in higher orbit are used to measure the temperature of the same volume of atmosphere that the radiometer is looking at. The GPS-RO temperature measurement can then be used to calibrate the radiometer.

Small satellites such as CubeSats play an increasingly important role in exploration, technology demonstration, scientific research, and educational investigations at NASA, including — planetary space exploration; Earth Observations; basic earth and space sciences; and developing pioneering scientific instruments such as advanced laser communications, satellite-to-satellite communications, and autonomous motion capabilities.

Click on Deccan Chronicle Technology and Science for the latest news and reviews. follow us on Facebook, Twitter.


Comments are closed.