Europe says goodbye to the Proba-3 solar eclipse

“This ambitious ESA mission has been in development for many years because its goal is to do something in space that has not been possible until now,” explains ESA mission director Damien Galano.

Once in orbit, the two Proba-3 satellites will allow long-term observation of the Sun’s thin surrounding atmosphere, the corona, which until now has only been visible for brief moments during Earth’s solar eclipses. To do this, the shadow cast between both satellites must remain in a precise position, meaning that they must fly autonomously in formation with an accuracy of just one millimeter – about the thickness of a fingernail.

“ESA and our industrial and academic partners have worked hard to get to the point where the satellite is ready to fly. “We are a little sad to finally say goodbye to these unique satellites, but we are also very excited to move into the final phase before launch.”

Proba-3 will leave for India on Saturday, November 2, with a new launch date scheduled for December 4.

For the first time since the launch of Probe 1 in 20021, an ESA mission took off from India. The air freight company initially did not accept the spacecraft because the batteries were already installed, so there was a delay in transportation, which was resolved by removing the batteries and shipping them in a separate box.

The two Proba-3 spacecraft will be launched together on the Indian Space Research Organization’s (ISRO) PSLV-XL launch vehicle, which has the necessary power at a reasonable cost to launch the combined 550 kg pair into an elliptical orbit that will rise to an altitude of up to 60,000 NM from Earth before reaching just 600 km.

This high orbit is necessary because the pair will fly in precise formation for a planned six hours around their maximum altitude, where Earth’s gravitational pull will be lower, as will the amount of fuel needed to fine-tune their position.

The mission involved an industry team from fourteen ESA Member States, including Canada, led for ESA by SENER Spain, along with Airbus Defense and Space in Spain, which provides satellite platforms, and Redwire Space in Belgium, responsible for the mission’s avionics. pre-launch tests and post-launch operations.

GMV in Spain, specialized in training flights, and Spacebel in Belgium, as a software supplier, form the core industrial team.

The Royal Observatory of Belgium will control the primary solar corona instrument ASPIRICS (Association of Spacecraft for Polarimetric and Imaging Research of the Solar Corona) Proba 3, hosted on the Coronagraph spacecraft.

The mission’s other spacecraft, Occulter, equipped with a 1.4 m diameter disk, will be responsible for blocking the Sun for the Coronagraph spacecraft during a precision formation flight. On the solar side, it has its own instrument, the Digital Absolute Radiometer (DARA) for measuring solar total power for climate research, developed by the Physical and Meteorological Observatory of Davos (PMOD) in Switzerland.

The third instrument, built by the Catholic University of Leuven in Belgium, the 3D Energy Electron Spectrometer, will measure the dominant energies of angular-resolved electron spectra in the radiation belts surrounding the Earth, providing valuable data for space weather modeling.

The Proba-3 mission will be managed from ESA’s European Space Safety and Education Center (ESEC) in Redoux, Belgium, which is currently conducting an extensive pre-launch preparation and simulation campaign.

Read more about the Proba-3 industrial consortium here.