Black box recorders for satellites

The Earth is frequently buffeted by solar storms

By BBC News Online's Dr Damian Carrington

Space satellites are to get black box recorders which store the details of the moments leading up to disasters.

The project is driven by the massive losses in the space insurance industry. Companies lost $850m in 1998, after paying out $1.9bn in claims.

The concept is identical to that in aeroplanes - you get information up to the time of the failure

Dr Alan Rodger

The main focus will be on why some satellites mysteriously fail while in orbit. Increases in the flow of superfast particles from the Sun have been blamed, but no firm evidence has ever been gathered to support the theory.

The new data provided by the black boxes will help design more robust satellites or at least improve the information that insurers use to set premiums.

High flying particles

Scientists at the UK's Mullard Space Science Laboratory have been given a year's funding to build the prototype black box, starting on Monday.

The project's leader. Dr Andrew Coates, told BBC News Online that the device would measure the flow of the high energy particles flying through space.

"The fear is that these could be a dominant cause of on-orbit failure," he said.

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The black box will weigh about 500 grams and will take power from the satellite. If the power system fails on a satellite, Dr Coates said, data about conditions at the time of failure could be obtained from a nearby satellite, also carrying a black box.

Previous work has shown that the maximum of the Sun's 11-year cycle of activity coincides with higher rates of satellite failure. But though a number of high profile and expensive failures have been anecdotally linked to inclement space weather, no proof exists.

The failures, if they are caused by the bombardment of the tiny particles, result from charging. Slower moving particles would charge the outside of the satellite. If one part charged more than another, a damaging spark could result.

Faster moving particles may penetrate right inside the satellite and directly charge the electronic circuitry.

Heavy cost

The funding for the black box project, thought to be about £50,000, comes from the Tsunami consortium and the UK Department of Trade and Industry. Tsunami is a consortium of scientists and UK insurance companies charged with bringing the two groups together.

The research may be of great use to insurers but satellite operators may be reluctant to put the black boxes on board.

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Extra weight means more expensive launch costs, according to Dr Alan Rodger, a space weather scientist at the British Antarctic Survey, and current co-ordinator of the Tsunami project.

He added that satellites might also need to be redesigned to balance the new load and to allow for the extra source of heat. And, finally, a black box would require the operator to deal with another data stream from the satellite.

"But these are lots of little inconveniences, rather than a major hurdle. In 10 years time, putting a black box aboard might be the natural thing to do," said Dr Rodger.

Dr Coates agreed, suggesting that possible resistance from operators could be overcome by a financial incentive: "Operators could get a discount from the insurer for having a black box recorder on board."

Future designs

Daniel Collins, of satellite designers and manufacturers Space Systems Loral, told BBC News Online that adverse space weather is unlikely to be responsible for many failures.

"We already monitor over 3,000 parameters on our spacecraft. And in 99% of failures we know what went wrong and often why.

"But it would be good to measure solar storms because these do affect spacecraft and that cannot be modelled from the ground."

Mr Collins believes that putting a black box on every satellite and building up data over five to 10 years will benefit future satellite designs.

And he says the proposed 500g mass of the detectors is no burden on the 1,500 to 2,000kg commercial satellites being launched today.