Checked, shaken, chilled and not stirred

Date: 21 June 2018
Satellite: CHEOPS
Location: Airbus Defence and Space Spain, Madrid, Spain
Copyright: Airbus 2018

This summer, the CHEOPS satellite breezed through thermal tests in France and vibration tests in Switzerland, demonstrating that it's able to operate within the extreme cold of the area and conjointly appropriate face up to the mechanical stresses of launch.

Keeping the CHEOPS telescope and detector at a stable temperature is very important for getting correct measurements of the brightness of stars. Temperature variations of many degrees will cause tiny distortions within the telescope structure leading to artificial changes within the measured star brightness.

Even tougher needs apply to the detector: CHEOPS can live the minute changes within the apparent brightness of a star caused by the transit of associate degree exoplanet across the stellar disc, and its detector should be stable to at intervals a hundredth of a degree to confirm sensitivity to such tiny changes.

In orbit, the satellite is warm directly by the Sun, and it'll conjointly receive infrared radiation radiated by the world and daylight mirrored by the surface. In spite of those direct sources of warmth, all the external surfaces on CHEOPS are exposed to cold area and, if not heated, could simply reach temperatures as low as -200 degrees astronomer.

As the satellite orbits the world and turns to watch completely different target stars, the well-lighted areas can amendment all the time, inflicting temperature variations that, if not actively paid, might degrade the accuracy of planetary transit measurements.

Thermal vacuum tests that characterized the optical performance of the science instrument underneath the belief of adequate aboard thermal management, were delineated in CHEOPS journal #9.

The latest thermal-vacuum tests, that occurred between twenty Gregorian calendar month and a couple of August at the airliner Engineering Validation take a look at (EVT) facilities in the city, France, geared toward guaranteeing that the aboard thermal management systems can do their job once subjected to realistic in-orbit conditions. These are the primary thermal tests that are performed on the integrated science instrument and ballistic capsule platform at realistic temperatures.

The take a look at results haven't solely provided evidence that the thermal management systems perform properly which CHEOPS will operate in associate degree extreme thermal atmosphere, however, have conjointly come a wealth of knowledge that may be accustomed refine a 5000-node mathematical model of the spacecraft's thermal behavior. With this, it'll be attainable to accurately predict, by suggests that of laptop simulations, in-flight eventualities that are impractical to check directly.

Right when the thermal-vacuum tests were completed in France, the satellite was shipped to an urban center, Switzerland to perform mechanical vibration tests.