European space giant Astrium has won a 300 million euro contract to build a new probe that will give us our closest ever views of the Sun. ESA’s Solar Orbiter is due to launch in 2017 on a seven-year mission to study our home star and how it drives space weather which not only causes spectacular auroras but also can damage spacecraft electronics. 

The spacecraft will travel in an orbit that brings it closer to the Sun than the planet Mercury, at a distance of 42 million kilometres. That will be one of the closest approaches of the Sun by any spacecraft and to get there, Solar Orbiter will make a complex series of fly-bys of both Earth and Venus to get a gravitational boost.

Challenges will include surviving intense thermal radiation and protecting the probes instrument suite, while at the same time allowing those instruments to observe the Sun. This will be achieved by a heat shield and new solar array technology.

Astrium UK will lead a team of European companies who will supply various parts of the spacecraft. It is one of the largest contracts ever signed between ESA and a UK company.

The deal was signed at the Science Museum in London at a two-day event to mark 50 years of the UK in space. Instruments to be carried by Solar Orbiter are being developed in the US as well as various European countries. NASA will contribute the launch vehicle.

Prof. Giménez Cañete, ESA Director of Science and Robotic Exploration, said: “Today ESA awarded a very important contract in the space science domain to Astrium’s spacecraft design and build facility at Stevenage in the UK.”

“This is testimony to the important role that the UK has played in space flight since the launch of Ariel-1 in 1962 and it is testimony to the important role that the UK continues to play in space science.”

Solar Orbiter continues a long tradition of European Sun explorers, including Helios 1 and 2, Ulysses, and SOHO, all in partnership with NASA, as well as ESA’s PROBA-2.

They have all prepared the ground for Solar Orbiter to advance our understanding of how the Solar System works, one of the major scientific questions of ESA’s Cosmic Vision 2015–2025 programme.

Solar Orbiter will investigate the connections and the coupling between the Sun and the heliosphere, a huge bubble in space created by the solar wind that extends far beyond our Solar System. It is through this wind that solar activity can cause auroras and disrupt satellite-based communication.

To get a close-up view of the Sun and to observe the solar wind before it becomes disrupted, Solar Orbiter will fly to within 45 million kilometres of the Sun, closer than Mercury. It will image the poles for the first time, helping us understand how the Sun generates its magnetic field.