On 20 September, the Copernicus Sentinel-2C satellite tv for pc captured its first beautiful picture of the Moon, achieved by rolling the satellite tv for pc sideways in a novel manoeuvre. Though Sentinel-2C is designed for Earth remark, this picture – meant for calibration and cross-mission comparisons – exceeded expectations.
The picture, with a powerful decision of round 5 km, reveals notable lunar options, together with the Copernicus Crater, the Tycho Crater and the lunar seas: the Sea of Tranquillity, the Sea of Moisture and the Sea of Clouds. This showcases the flexibility of Sentinel-2C’s multispectral imager, which normally operates from its 786 km orbit to seize high-resolution knowledge of Earth’s land and coastal waters.
This lunar picture is a part of an everyday ‘Moon calibration’ course of. Roughly as soon as a month, the satellite tv for pc will roll sideways to picture the Moon as a substitute of Earth. The Moon’s well-known and steady gentle depth permits us to detect and proper even the smallest modifications within the instrument’s efficiency, which might happen because of getting older, reminiscent of optical coating degradation or detector drifts.
This course of ensures the ‘radiometric accuracy’ of the information stays exact all through the mission, a essential parameter for a lot of functions.
The uncooked knowledge initially displayed an elongated, eclipse-shaped Moon brought on by the relative movement between the Moon and the satellite tv for pc. A correction of this impact was carried out to understand this implausible picture.
Launched on 5 September 2024, Sentinel-2C joins its twin satellites in orbit persevering with to ship invaluable high-resolution imagery for the Copernicus programme.
