Success Stories

Canadian company keeps satellites safe from the Sun

A warning system needed for solar flares

Dielectric materials are abundantly used in spacecraft design, on spacecraft exterior surfaces such as solar cells, optical components, and thermal blankets as well as on the spacecraft interior such as printed circuit boards. The use of dielectrics in spacecraft design cannot be avoided.

The presence of high-energy particles in the space environment is a natural phenomenon. The Sun is an active body with flares and eruptions occurring continuously. With each flare or eruption, high-energy particles are released into the space environment. All orbiting spacecraft encounter these high energy particles.

The high-energy particles emitted during solar flares can penetrate the spacecraft and deposit an electrical charge inside the dielectric material. This process, called deep charging, is capable of disrupting a satellite's instruments or even producing a catastrophic systems failure.

Since solar flares can't be prevented the risks presented by these high-energy particles remain. However, a Canadian company called DPL Science has now devised a way to warn satellite operators that a deep charging incident may be imminent, so that they may act in a timely manner to protect the satellite from damage.

DPL's monitor is up to the task

DPL Science, a Montreal-based firm, designed the Dielectric Deep Charge Monitor specifically to address the problem of deep charging on satellites. The Canadian Space Agency's (CSA) Space Technology Development Program (STDP) supported the effort through a $600,000 contract, while DPL contributed another $1.2 million to the project.

The early-warning device is about the size of a paperback novel and consists of an electronics module and a sample holder. The Charge Monitor is mounted such that the electronics module is located inside the spacecraft structure while the sample holder—which contains a dielectric material sample—is directly exposed to space.

The Charge Monitor's electronic module continuously monitors the sample, looking for early signs of a possible dielectric discharge. Should the charge on the dielectric sample approach its electrical breakdown level, the Charge Monitor immediately alerts the satellite operator. The operator can then take preventive measures, such as temporarily turning off sensitive instruments, turning on heaters near the breakdown site, or delaying critical spacecraft operations.

Monitor set to debut in space

The Charge Monitor is expected to make its debut in space aboard the CSA Maritime Monitoring and Messaging Microsatellite (M3MSat). The micro-satellite, designed primarily to track and identify ships at sea, is set to be launched into a low Earth orbit (LEO) sometime in 2012. By comparing the data gathered by the device to mathematical predictions and ground-based measurements, DPL engineers expect to establish flight heritage for the Charge Monitor while also providing valuable science data for LEO applications.

Clearly, the continuous monitoring of dielectric deep charging in space helps satellite operators protect against its hazardous effects. But the Charge Monitor is fully capable of delivering additional spin-off benefits back on Earth. For example, it can be used to perform ground-based and space-based material testing under simulated solar storms. This can give satellite designers and builders crucial information on the behaviour of the materials that may help guide the construction of satellites.

Testing facility only one of its kind in Canada

And, while the Charge Monitor has yet to prove itself in space, a permanent symbol of its success is already in place at DPL Science. As part of the project, the company built a Spacecraft Charging Thermal Vacuum Test Facility dedicated to deep charging material testing. The only one of its kind in Canada—and one of just a handful in the world—the facility is able to simulate the energetic space environment. This allows Canadian scientists to locally perform ground-based testing of spacecraft materials for deep charging assessment.

As a result of its work on the Dielectric Deep Charge Monitor, DPL's ability to compete in the global aerospace industry has been greatly enhanced—a remarkable achievement for a small company run by two highly qualified Canadian engineers. The company now boasts additional expertise, new facilities and enhanced core capabilities.