Small Wonder

by cynthia Macdonald

photography by Mike Ford

The world’s first satellite wasn’t much bigger than a beach ball, but its impact on history was truly massive. Launched into orbit almost 60 years ago, Sputnik 1 marked the start of the “space race” between East and West.

Yet this humbly beeping sphere wasn’t just a symbol of Cold War brinksmanship; its real purpose was to gather useful information about the nature of space. Thousands of Sputnik 1’s successors now circle the Earth, carrying payloads that perform a variety of functions. Some collect space data and others facilitate global communication. Satellites help us to navigate our planet, to understand its every physical detail. And today, they play a central role in the study of – and the fight against – climate change.

Global warming is among the gravest problems of our time. York University has no shortage of thinkers grappling with its challenges, at the levels of science, business, communications and government policy. As you’d expect, most of these great minds are busy examining changes on Earth. But the greenhouse effect is an atmospheric problem – one that harms our planet, even as it takes place outside it. If the problem isn’t attacked at the extraterrestrial level, it stands little chance of being solved.

“Climate change is a global phenomenon, and different parts of the globe respond differently to it,” says Gordon Shepherd, professor emeritus of earth and ­atmospheric science at York’s Lassonde School of Engineering. “While ground-based measurements provide valuable information about specific locations, ­satellite observations are the only way to cover the entire planet. For that reason, the entire Earth must be observed.”

That’s why the work being done by scientists and engineers in York’s well-known space programs is of critical importance right now. “We have a unique ­capability within Canada to bring brainpower together and come up with a new way of monitoring this problem,” says Regina Lee, chair of Lassonde’s Department of Earth & Space Science & Engineering (ESSE).

Satellite observations
are the only way to cover the entire planet

Other universities offer space science programs and, like York, they regularly partner with the Canadian Space Agency to work on international missions. But York is different in that it also offers a unique education in space engineering. “Our aim is to have engineering support science, and get the science program to drive engineering into new technologies and capabilities,” says ESSE Professor Tom McElroy, who holds the CSA/ABB/NSERC Industrial Research Chair in Atmospheric Remote Sounding. “This isn’t often done, because the specialties and timescales are very different.”

As aerodynamics expert Theodore von Kármán once wrote: “The scientist discovers that which exists. The engineer ­creates that which never was.” Scientists like McElroy ­identify problems, collect data and analyze it; engineers like Lee develop infrastructure and systems, such as satellites and spacecraft, to support that process. (On that note, the term “rocket scientist” – often used to denote a smarter-than-­average person – turns out to be somewhat erroneous. People who create rockets, while educated in scientific principles, are always engineers).

McElroy is a perfect fit for Lassonde’s mission of teaching “renaissance engineers” who can slalom effortlessly between disciplines, and that’s because he is one of the country’s foremost “renaissance scientists.” Fascinated by robotics since grade school, he ultimately became a designer and builder of scientific instruments – one of which, intended to ­measure electromagnetic waves in space, was tested by astronaut Marc Garneau on the Challenger shuttle in 1984. A similar apparatus was flown by York alumnus Steve MacLean (PhD ’83) on Columbia in 1992.

But McElroy is best known for two inventions that, while ground-based, were also created to evaluate changes occurring high above in the atmosphere – changes that were having an effect on people’s health and well-being. Now used in more than 45 countries, the Brewer Ozone Spectrophotometer was initially invented to monitor the atmosphere’s ­thinning ozone layer. Later, it was adapted to measure increasing amounts of harmful UV radiation that were reaching the ground as a result.

And the UV index – which McElroy co-invented in 1992, during his time as a research scientist with Environment Canada – is even better known. It has been credited with ­saving thousands of lives around the world by increasing ­public awareness of the sun’s potentially damaging properties.

Ozone is considered one of the “good news” stories in ­climate change. Scientists like McElroy were able to show that human activity (specifically the widespread use of chlorofluorocarbons, found in refrigerants and aerosol sprays) was contributing to ozone depletion. After their revelations were made, a campaign of evidence denial ensued that foreshadowed the global warming denial of today. But, says McElroy, “eventually the science won out, and industry agreed to solve the problem.”

The highly successful international treaty that was struck to ensure this, known as the Montreal Protocol on Substances that Deplete the Ozone Layer, will mark its 30th anniversary next year. Recently, satellite pictures have revealed that the ozone layer is slowly starting to repair itself. Without the concerted effort of science, government, industry and the public, NASA has calculated the rate of skin cancer today due to UV radiation might now be 650 per cent higher than it is.

Convincing interested parties to reduce carbon dioxide and methane emissions will be a taller order, McElroy concedes. But he thinks it can be done. “You have to believe that it’s possible to make this huge change,” he says. “I’m sure people didn’t think it was possible to turn off coal-fired electricity in Ontario, because Nanticoke was the largest generating plant in North America. But now it’s gone.”

Visual evidence of thinning ozone, gathered by satellite cameras, was one of the things that helped convince people that action needed to be taken. Today, satellite images of dwindling sea ice at both poles are also proving to be a powerful weapon in the effort toward greenhouse gas reduction.

Like McElroy, York geophysicist Christian Haas, the Canada Research Science Chair in Arctic Seas Ice Geophysics, uses satellite technology to complement what he does on the ground or from an airplane. He is an expert on the disappearance of sea ice, one of the most famous results of climate change. Via a combination of measuring techniques, scientists have estimated that sea ice in the Arctic Ocean could be reduced to half its 20th century volume by the middle of the 21st.

Combining techniques is key in Haas’s work – these include measurements taken in space and sky and on ground (even underground, since thawing permafrost may be releasing large amounts of greenhouse gas).

McElroy believes that with today’s more sophisticated techniques, pictures of the melting Arctic could prove even more compelling to the public than earlier pictures of a growing ozone hole. This type of new instrumentation could “map pollution in the Arctic, and watch the evolution of methane as the permafrost thaws during the summer,” he says.

Satellites that used to be the size of a school bus
are now going to be as small as a Chinese takeout box

Such a device could well emerge from an important facility now being planned at York. Next year, Lassonde anticipates the opening of its new Suborbital Payload Research Centre – a state-of-the-art design, building and testing facility.
The centre will feature a strong emphasis on microfabrication technology – remote sensors that were once big, cumbersome and expensive will be reduced to thumbnail-sized computer chips. Whereas Sputnik 1 was small, satellites that followed in its wake were much larger (and cost a lot more to boost into space as a result). Now, the scientific tide is turning. “Satellites that used to be the size of a school bus are now going to be as small as a Chinese takeout box,” says Lee.

The advent of “CubeSats” is now greatly reducing the cost of sending data-gathering technology into space. Shuttle missions designed to orbit the Earth once cost up to $200 million each; suborbital nanosatellites can be carried into space (by balloons, aircraft or sounding rockets) for a tenth of the price. Consequently, many more satellites can be deployed, enabling scientists to acquire a much richer picture of climate change causes and effects.

In addition to disappearing sea ice, nanosatellite pictures can theoretically count every animal of a given threatened species, every tree lost to deforestation or sea creature lost to overfishing, and every CO2-emitting vehicle on the roads. “There are lots of areas where air traffic is not being tracked, for example. With nanosatellite constellations, we’ll be able to do that,” says Lee.

Nanosatellites are already examining other potential causes of atmospheric disturbance, beyond greenhouse gases. “One of the things we are involved in is measuring the magnetic field around the Earth,” says Lee, “which used to be done much more expensively, by big satellites.” Fluctuations in this field can cause earthquakes, which satellite data could help predict – resulting, again, in countless saved lives.

Microtechnology will also make the complicated testing process much easier. Large instruments that go into space must be rigorously tested to withstand its harsh conditions. They are placed in helium-flooded thermal vacuum chambers with a temperature of -260 C, sometimes for up to a month. In the small cleanroom at York, that process will be hastened and cheapened by being brought in-house.

Interplanetary exploration is naturally of great interest to York space researchers. And though it may not seem so, this research is linked to climate change questions as well. Discoveries made by teams from York’s Centre for Research in Earth & Space Science can also have an impact on Earth. In 2008, York-designed weather instruments on the Phoenix Mars Lander revealed heretofore unseen pictures of snow falling from clouds on the red planet. Mars and other planets experience climate variability too, though of course it isn’t anthropogenic (caused by people) in nature.

What happens on other planets is still instructive as a subject of study. Venus, for example, experienced a greenhouse effect when large amounts of water on the planet evaporated, releasing a great deal of water vapour (itself a greenhouse gas) into the air. As a result, Venus is now the hottest planet in our solar system.

All this means that every researcher in the field of space – whether scientist or engineer, whether concerned with Earth or other planets – has a vested interest in the study of climate change. One of the reasons Lee cites for scientists and engineers to band together is that when researchers pool their findings on climate change, the likelihood that the government, business and consumer sectors will be persuaded by them is greater. Too often, parties remain within their own spheres of interest. But that’s changing.

At York’s Suborbital Payload Research Centre, the design, testing and launch of a typical nanosatellite mission will take place over the span of an average MSc degree, which would provide students with the chance to participate in the process from beginning to end.

“More has been learned about this planet from space in the last 40 years than in all previous history,” wrote science journalist William E. Burrows in his 2006 book The Survival Imperative: Using Space to Protect Earth. And even greater advances have been made since then. In the past, space research has sometimes been marred by its association with military posturing, obscure experiments and disasters that were costly not only in monetary terms, but in those of human life.

No more. The new space race is about something very different: creating technology designed to preserve and protect humanity from the ravages of a rapidly warming Earth. It is a race that scientists and engineers at York University are in a very good position to win.  ■

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