UCL technology analyses Sun’s effect on Earth

Scientists at University College London (UCL) are hoping to learn more about how solar activity affects the Earth by developing technology for Europe’s next space-science mission.

The UK Space Agency last week awarded £3.7m to help scientists prepare for three missions that the European Space Agency is considering: the Solar Orbiter satellite, the Euclid telescope and the PLATO space observatory.

Although only two of the missions will go ahead, members of UCL’s Mullard Space Science Laboratory (MSSL) are optimistic that Solar Orbiter will be the first ready for a launch in 2017.

The team, led by principal investigator Prof Chris Owen, is developing an instrument for the mission that analyses the matter the Sun fires out into space. This could help us to better understand the effects of this ‘solar wind’ on the Earth, our satellites and spacecraft.

‘As we put more and more technology into space we are more vulnerable to this solar weather,’ Owen told The Engineer. ‘It can even knock out satellites.

‘And with our future inclinations to go to other planets, understanding the environments astronauts will face is important.’

The MSSL team is part of an international consortium with institutions in France, Italy and the US that is designing a solar-wind analyser for studying the different particles found in solar matter − namely electrons, protons, alpha-particles and heavy ions of iron and carbon.

‘Our expertise is focused on the electron instrument, which will be able to characterise how much energy the electrons have and what direction they are coming from,’ said Owen.

‘This will give us a fingerprint of what’s happening back on the Sun and we want to link that with what we see in space.’

The electron sensor will be placed on a boom jutting out from the Solar Orbiter so that it remains in the craft’s shadow. But part of MSSL’s challenge will be ensuring that the device can withstand temperatures of several hundred degrees, as well as the extreme cold of space, in case the trajectory is altered and the sensor comes into full view of the Sun.

‘We will also be collecting a huge amount of data but will sometimes be very far from the Earth, so the software engineering needs to maximise how much valuable data we can process before sending it back to Earth,’ said Owen.

Because of spending constraints, the craft will only travel as close to the Sun as Mercury − equal to other missions and less than originally proposed. This will allow it to share technology with ESA’s proposed Mercury mission, Bepi Colombo.

‘Scientists always ask the engineers to get as close as possible but this isn’t a mission killer,’ said Owen. ‘In cases where we will be looking at the same part of the Sun for a long time, it will be around 26 days rather than 30 − and these are all fairly small changes.’

ESA will decide whether to go ahead with Solar Orbiter when it chooses two of the three proposed missions in June 2011. Owen is confident that, should the mission go ahead, the solar-wind analyser will be included.

‘Only a complete failure of engineering or going very over budget would stop it – this is one of the key instruments,’ he said.

UCL has received around £920,000 for the project, but the US international partners are relying on funding from NASA, which is up for review in September. ‘We need to work hard to make sure they don’t pull they plug,’ said Owen.