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On December 5, the Indian launch vehicle PSLV-XL successfully launched a pair of European satellites of the Proba-3 mission into orbit. They are designed to study the solar corona — the most rarefied and hot layer of our star's atmosphere, the temperature of which is millions of degrees.
To cope with this task, the engineers of the European Space Agency (ESA) built two devices. One of them will play the role of an artificial moon for the other. Currently, the vehicles are in a high elliptical orbit with a perigee of 600 kilometers and an apogee of 60 kilometers.
The satellites will remain tethered to each other for the coming weeks until engineers complete a functional check of all their systems. Then, at the beginning of 2025, the separation of the devices will take place: they will separate at a distance of 144 meters (their position relative to each other will be controlled with an accuracy of millimeters).
If all goes according to plan, observations of the solar corona will begin around April 2025. The first apparatus will cover the Sun for the other, which will make it possible to observe the inner layers of the solar corona.
