NASA’s Largest Satellite Antenna Ever Has Just Unfurled in Space
A flower -shaped satellite “Fleuri” in space, unfolding to reveal the largest radar antenna reflector ever put into orbit. The NASA-ISRO synthetic opening radar (Nisar), a joint project between the American space agency and the Indian Space Research Organization (ISRO), was launched on July 30 from the satisfaction of Dhawan Space Center in southeast India, before moving to its real size 17 days later.
The spaceship is now ready to make large -scale observations of the earth and will use the radar to follow the changes on the surface of our planet in an unprecedented resolution. It can record the movement of glacial caps and glaciers, cruustal deformation caused by earthquakes and landslides, and changes in forest ecosystems and wetlands, up to a precision of a few centimeters for certain types of land. The objective is that Nisar data helps decision -making in a wide range of areas, including responses in the event of a disaster, infrastructure, agricultural policy and food security.
“The successful deployment of the Nisar reflector marks an important step in the capacities of the satellite,” said Karen St. Germain, director of the Terk Sciences Division at the NASA headquarters, in a press release.
A satellite with two eyes
Nisar antenna reflector – the device he uses to transmit and receive radar signals – measurements 39 feet in diameter, which makes them the largest device ever orbit by NASA. Made from gold -plated metal mesh, the reflector was attached to the satellite as a folded umbrella. During the four days which followed the launch, the satellite slowly extended its boom, before the framework of the antenna, which had been held under tension, was released on August 15, allowing the reflector to “flower” to its large size.
Nisar is the first satellite to transport two types of synthetic opening radar: L strip and strip S. The first penetrates the forest canopy and the clouds to detect the crustal deformation and the movement of the ice cap. The band is sensitive to the humidity of the snow cover and changes in the vegetation. By combining both, it is possible to record a multilayer recording of various phenomena ranging from earthquakes and volcanic activity to deforestation. The giant reflector serves as an essential “eye” for the two systems, concentrating the radar transmitted when sent to earth and receiving and concentrating these signals when they bounce on the satellite.
“The synthetic opening radar, in principle, works like the lens of a camera, which concentrates the light to make a clear image. The objective of the objective, called the opening, determines the clarity of the image,” said Paul Rosen, scientist of the Nisar project to the Jet Propulsion Laboratory, in a press release. “Using special interferometric techniques that compare images over time, Nisar allows researchers and data users to create 3D changes of changes that occur on the surface of the earth.”
Technology from decades in manufacturing
The NASA jet propulsion laboratory has been developing radars to be used on satellites since the 1970s, launching the first oceanic observation satellite in the world, Seasat, in 1978, and revealing the topography of the surface covered with Venus clouds with the Magellan planetary probe in the 1990s.
The culmination of knowledge acquired over the decades, Nisar is a product of American and Indian technology: NASA has provided SAR in L band and data communication equipment, while India’s ISRO was responsible for Sar S-Band and satellite auto-bus-the infrastructure that manages power, communications and orientation of the satellite. The Isro land station was responsible for the launch and initial operations, and experts from the two countries worked together to monitor deployment operations.
