While the recent third-stage failure of a Proton rocket launch brought risks in space enterprise into sharp focus, experts tell us that historically there are many other worrying scenarios.
Mitigation techniques against charging effects should be detailed in satellite technical presentations to insurers, to allow for better risk assessment
Denis Bensoussan, a senior underwriter for space risks at Hiscox Lloyd’s Syndicate, says, “The Galaxy 15 event, in 2010, dramatically reminded the space industry of the worrying scenarios related to space environment.”
In April 2010, Intelsat’s Galaxy 15 satellite stopped responding to commands. After several months of uncontrolled drift, Galaxy 15 was eventually recovered by combined Intelsat and orbital actions.
Satellites, according to Bensoussan, are specifically designed to prevent the risk of loss of control. However, when control is lost “errant satellites are tracked and monitored and catastrophic consequences to third parties have so far been avoided or mitigated or self-cured”.
Nevertheless, the rapid proliferation of space debris has increased the frequency risk for such occurrences that have, in turn, raised awareness among the space industry and the public at large.
The main culprit of lost satellites is reportedly internal causes including launch vehicle under-performance or failure, leaving the satellite in a useless orbit or a mechanical failure owing essentially to factors such as power, propulsion and so on. The external causes, according to Bensoussan include space weather-related environment, space debris and accidental or intentional physical or nonphysical interferences from other spacecrafts or from the ground.
“The space weather-related charging environment is the current major external contributor, although it was already identified as a threat in the 70s,” says Bensoussan.
Mitigation techniques have been defined in ISO-14302, ECSS-20-06 and ECSS-20-07 norms. Furthermore any failures caused by the charging environment are covered under standard property damage, all- causes, insurance policies.
However, several major solar events have been surveyed, Bensoussan says, and in each case, only few satellites have suffered from the harsh environment.
“The Carrington event (powerful solar storm in 1859) was considered as the absolute threat, but was only three time larger than the huge Halloween day event of 2003,” he adds.
“However, smaller solar events are not without consequence and can sometimes be serious. In each case, primary lack of robustness was established due to a design or manufacturing flaw and an improvement was possible.”
Insurance experts believe that more careful design or manufacturing and full application of norms should be recommended, and the lessons learnt should be made accessible to all concerned. In addition, Bensoussan believes, “Mitigation techniques against charging effects should be detailed in satellite technical presentations to insurers, to allow for better risk assessment.”
More than 12 satellites lost for causes attributed to space weather effects including
– ATS-5 (August ‘69): 1st GEO voltage measurement
– DSCS-2 (November ‘71): 1st mission lost by overloading of primary power
– SCATHA (launched January ‘79): Satellite dedicated to charging analysis
– Skylab loss in 1979 due to high solar activity
– Great geomagnetic storm of March 1989: Four GPS satellites out of service for a week.[/boxposthighlight]