A collaboration between two University of Alberta professors may finally have led to a breakthrough: a new radiation detection device with unique capabilities that could not only help us prepare for radiation bursts in space, but save the lives of astronauts at the Lunar Gateway or on the Moon.
The device is called the “Sweeping Energetic Particle Telescope.” or SWEPT. It’s a radiation-detection device at its heart, and a quick glance at the prototype reveals the familiar tubular shape of a telescope or camera, including a rotating attachment point that lets the scope pitch and yaw just like terrestrial telescopes do. This combination of shape and mobility lets it determine the vector (speed and direction) of the particles, which could be vital in protecting Artemis astronauts.
In an interview with SpaceQ, University of Alberta (UofA) professors Ian Mann (of the UofA Physics Department) and Robert Fedosejevs (of the Electrical and Computer Engineering Department) explained more.
Professors Collaboration
Mann and Fedosejevs have a long history of collaboration on radiation detection. Mann is a former Canada Research Chair in Space Physics (2003-2013), and was recently inducted into the Royal Society of Canada for his work studying space radiation, while Fedosejevs has extensive experience working with high-energy radiation with a particular focus on laser fusion energy.
When Mann took up the Chair, he was interested in Fedosejevs’ work in measuring radiation, and they began working together on the “Outer Radiation Belt Injection, Transport, Acceleration and Loss Satellite” (or ORBITALS), which was intended as a Canadian contribution to the international Living With A Star program that was going to “provide a unique view of the largely previously unexplored inner magnetosphere,” helping us better understand the “global dynamics and morphology of the Earth’s radiation belts.”
ORBITALS never got off the ground; Mann explained that the global financial crisis made it unviable, especially considering it predated the current era of comparatively-inexpensive launch into LEO. Yet though ORBITALS never flew, the collaboration remained, as their teams turned to working on SWEPT in 2011.
Developing SWEPT
At its core, SWEPT seems comparatively simple. The idea behind the telescope is to be able to track the type and velocity of space-based radiation that’s hitting the spacecraft that SWEPT is attached to. While most detectors only really show how much radiation there is, SWEPT shows where it’s coming from, what it is,and how fast it’s going.
In order to do that, the device is built around directed detection. It’s heavily shielded on all but one side, with a small aperture that lets radiation in to be detected by a series of silicon plates, and (as said earlier) can be mechanically turned to face in different directions. By analyzing the plates, computers attached to SWEPT can determine which kinds of energetic particles are coming in, how quickly they’re moving, and how many are present.
The current SWEPT device has two modes: one where it slowly scans across its entire range, and another that responds to bursts of radiation (particularly solar energetic particles, or SEPs) where it focuses in a particular direction and scans frequently in a small area. This can not only provide a lot of scientific data, but serve as a valuable early-warning device, as Mann and Fedosejevs detailed later.
Nevertheless, it’s not as easy as it seems. SWEPT has been in development since before 2011—when they received their first Canadian Space Agency (CSA) award for a version of SWEPT intended for the International Space Station—and Fedosejevs explained that the lengthy research is partially because “the sweeping motion is not trivial.” Having a telescope that continuously moves by itself and doesn’t rely on movement of a satellite is rare and comparatively novel. Other moving parts on space hardware will usually only move “once in a blue Moon,” he said, but SWEPT will be continuously moving and scanning and therefore will require rugged rotation hardware.
SWEPT is also fairly massive, as it requires heavy shielding on its sides to keep out the energetic particles, which can complicate the problem.
It took time for his UofA team and their partners at ComDev (later Honeywell) to develop and perfect the sweeping mechanism, considering those restraints. But he’s confident that they’ve succeeded. He said that Honeywell has already tested the rotation mechanism up to 75,000 rotations, “which is essentially what we consider a five year lifetime for the instrument,” and his team has recently completed instrument-testing at the TRIUMF particle accelerator.
His recent presentation to the Canadian Lunar Workshop showed that the instrument has a technological readiness level of 5 with a “low risk path to TRL 6,” and which puts it at the point where it’s ready to be demonstrated in space. If SWEPT were to be built for deployment, Fedosejevs said, it would be built by Honeywell, and he was confident it could be done without issue.
Lunar Gateway and Lunar Safety
SWEPT has been the subject of several CSA awards going back to 2011, including a recent 2021-2023 STDP award of $899,000 for the “P-SWEPT,” or Planetary SWEPT. While the 2011 SWEPT project was focused on potential deployment on the International Space Station (ISS), P-SWEPT has been developed with an eye to deployment on the Lunar Gateway.
Mann said that studying radiation on the Gateway is vitally important. “The plans with Artemis and the Lunar Gateway is an area of radiation risk for deep space exploration, and we want Canada to be at the forefront of understanding what that risk and that radiation looks like,” as well as how best to protect astronauts from the risk.
In Low Earth Orbit, including on the ISS, Earth’s magnetosphere still mostly protects astronauts and equipment from radiation, including the potentially dangerous SEPs. Outside of it, these will be far more of an issue, even on the Lunar surface. Mann said that it was incredibly lucky that none of the Apollo missions were affected, as “a severe event would probably have been catastrophic,” and Artemis astronauts need to be prepared and aware considering how long they’ll be outside of the Magnetosphere.
SWEPT will help tremendously in two different ways. As a scientific instrument, it will aid us in better understanding how SEPs work and what to expect. The effect of magnetic fields, and the ebb and flow of the cosmic wind, mean that particles may not come from where you’d expect them to, and that simply protecting yourself from the sun may leave you vulnerable to a burst from a different direction. SWEPT will help us better understand how that works.
More practically, though, it can serve as an early-warning device. SWEPT can detect bursts of electrons and, using its sweeping motion, pinpoint exactly which direction they’re coming from. As electrons move faster than protons and neutrons, they’ll hit the station first—creating an opportunity for an “early warning system” for oncoming particles that will allow astronauts to move into protected areas (like shielded Gateway modules or under Lunar regolith.)
Mann said that SWEPT should give up to half an hour of warning.
Mann also said that these threats are “sporadic,” and truly dangerous ones may only come “once every few years.” As the Gateway is only expected to have crew a month out of every year, so a dangerous SEP may not happen when humans are anywhere near it. But if it does happen, and if there are astronauts on the Gateway or on the surface, SWEPT will provide them the warning they need to protect themselves. Mann called it “actionable headroom.”
Will it Go to Gateway?
Mann believes that as a directional early-warning telescope that is massive enough to be most suitable for larger installations like the Gateway, SWEPT will be “the right detector in the right place.”
Yet it’s still up in the air as to whether they’ll get the opportunity. Fedosejevs’ workshop presentation was as much a pitch as anything else, saying that SWEPT is “ready to deploy on future missions,” and that it complements the HERMES and ERSA detectors from NASA and the ESA respectively. Any decision on adding SWEPT to the Gateway would require a consensus of all the agencies working on Gateway, Mann granted, which may be difficult considering it is new technology.
Still, there’s grounds for optimism. Fedosejevs said that “we’re very confident that it is essentially ready to design, build and fly if we were given the funding,” and Mann pointed to a recent Government announcement of $76.5 million over eight years “in support of Canadian science on the Lunar Gateway” as a positive sign that they’re “very well placed for.” He’s confident that they have “the science, maturity and the technical maturity, to be able to start development at low risk.”
He knows that there will be “some small ‘p’ politics, maybe even big ‘P’ Politics between the different space agencies,” but also believes that “it would be better to put our radiation detector up as soon as possible so that you get the highest fidelity measurements of the radiation fields.” He closed by saying that “we’ve been discussing with the Canadian Space Agency, what the schedule would look like in relation to implementation at different points in the Artemis schedule,” and that it will come down to ensuring that “what [the CSA] wishes to do chimes well with what the other international space agencies are also wanting to do.”