View of Earth from a 6,000 km orbit through a 2 mm lens

Equipped with a miniature camera, the TRISAT-R CubeSat captured unique images of the Earth from 6,000 km, contributing to ESA’s research on medium-Earth orbit and digital imaging effects.

Partially shadowed Earth in the distance as seen from orbit at an altitude of 6,000 km (3,700 miles). This unusual image was obtained using a very small camera. It measures just 2 mm (0.08 inches), about the size of the end of a 20 euro cent (or US nickel). This is part of a small-scale technology experiment carried out on his shoebox-sized TRISAT-R CubeSat at ESA.

Iztok Kramberger, TRISAT-R project manager at the University of Maribor, explains: “This tiny camera, less than 2 cubic millimeters in size, captured images of an object of about 1 trillion cubic kilometers – our beautiful Earth – from thousands of kilometers away.”

A CubeSat made from three standardized 10 cm (4 inch) boxes, Trisat R This is Slovenia’s second space mission, with Europe’s first Vega-C launch last year reaching the relatively harsh environment of medium-Earth orbit at an altitude of 6,000 km (3,700 miles). The mission’s orbit passes through the core of the ionosphere (the electrically active layer of Earth’s atmosphere) and the inner Van Allen radiation belt.

The side cover size of TRISAT-R CubeSat is 10×10 cm. In the center you can see the photodiode (the white part in the middle) and the camera (the small black dot next to the diode and directly above the image). In the center of the camera, you can see a 2 x 2 mm camera lens with a 120 degree field of view. The lens is made from clear, radiation-resistant borosilicate glass and is attached directly to the image sensor below, providing 320 x 320 pixels.Credit: University of Maribor

This will enable TRISAT-R to test a range of radiation detection payloads. In addition, the TRISAT-R team mounted his two miniature cameras with lenses made of clear borosilicate glass directly onto a 320×320 pixel image sensor to provide limited radiation resistance. Ta.

Dr. Cranberger added: “These highly miniaturized cameras are not intended to perform ground imagery, so the resulting images of the Earth are very low resolution. Also, the TRISAT-R satellite uses magnetorque for attitude control. accurate pointing is difficult to achieve.

“Our main interest was in capturing an example of the ‘black sun effect’, which is common in terrestrial digital image processing, where pixel oversaturation can cause very bright areas to appear dark. We were successful in these investigations and were fortunate to be able to obtain images like this one. ”

ESA supported the manufacturing, assembly and testing of TRISAT-R through the ‘Fly’ element of the Integrated Support Technology Program, opening up on-orbit demonstration opportunities for European companies.

Located in a unique and challenging orbit, TRISAT-R’s commissioning phase is scheduled to conclude later this month, including 16 months of successful on-orbit operations.