Belgian satellites to study the sun’s corona in most accurate trajectory ever (VIDEO)

It was at 11.34 am CET that the 2 satellites were blasted into space on an Indian space research organisation (ISRO) rocket.

It was a first important step, but certainly not the last. The 2 satellites have to spend the next 2 years in an elongated orbit around Earth, at a distance of between 600 and 60,000 kilometres from our planet.

The 2 satellites must fly through space in a perfect trajectory, exactly 144 metres apart. It’s quite a feat, because the margin of error is only 1 millimetre. It is the first time satellites will fly in such accurate formation.

Artificial solar eclipse

This precise trajectory is necessary to create an artificial solar eclipse. One satellite must cover the sun for the second satellite that carries a special telescope. This so-called coronagraph will be used to examine the sun's atmosphere.

Because only then will the atmosphere, the solar corona, be visible. The corona is several million degrees Celsius hot, while the surface of the sun is much cooler at ‘only’ 5,500 degrees. At present we do not know the cause of this temperature difference.

By studying the solar atmosphere, scientists also hope to be able to predict space weather more accurately. Solar storms can disrupt Earth's magnetic field to such an extent that communication and navigation systems malfunction.

Proba-3 is ESA's fourth Proba mission, following previous launches in 2001, 2009 and 2013. The mission is a collaboration between 15 ESA countries led by Sener, a Spanish company. The coronagraph was developed under the leadership of the Centre Spatial in Liège. Belgium’s Royal Observatory is in charge of the scientific research.

The mission will cost around 200 million euros. The first images of the solar corona are expected in four months’ time.