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March 31, 2021

ISIS-II space mission launched ݮƵ’s international reputation for auroral research

Faculty of Science space physicists celebrate Canadian-built satellite’s 50th anniversary
ISIS-II
ISIS-II ݮƵ Archives

Fifty years ago, the ݮƵ’s fledgling space research program literally achieved lift-off, with the launch of the Canadian-built .

“ISIS-II represented the central role that the ݮƵ played in the initiation of the space age for Canada,” says space physicist Dr. Eric Donovan, PhD, professor in the in the .

I don’t think our space research group would exist in anything like its present form, if we didn’t have ISIS-II.

The ISIS (International Satellites for Ionospheric Studies) , a joint Canada-U.S. venture, included two new made-in-Canada satellites for studying the ionosphere and the aurora borealis (northern lights). ISIS built on the success of Alouette 1, Canada’s first satellite, launched in 1962.

In 1960, at what was then the Calgary branch of the University of Alberta, the three-year-old physics department took over operation of the Cosmic Ray Station, an observatory built atop Sulphur Mountain in Banff National Park. This helped establish the department’s research into high-energy particles in space which, as serendipity would have it, was the focus of the ISIS program.

ISIS-II was launched on March 31, 1971 aboard a Delta rocket, from the Western Test Range at Vandenberg Air Force Base in California.

The satellite carried an auroral scanning photometer, built by RCA Victor in Montreal. The instrument was based on scientific design requirements developed by then-ݮƵ space physicist Prof. Cliff Anger and Prof. Gordon Shepherd at York University. The photometer scanned the aurora in visible light. 

Mounted atop the satellite, the photometer “was extraordinarily innovative for its time,” producing high-resolution images with a spatial quality that hasn’t been equalled since, says Donovan, co-director of ݮƵ’s Auroral Imaging Group.

Data from telemetry and the Auroral Scanning Photometer instrument aboard the ISIS-II satellite was processed by the imaging team at ݮƵ using the then-state-of-the-art Digital PDP-8i computer.

Data from telemetry and the auroral scanning photometer instrument aboard the ISIS-II satellite was processed by the imaging team at ݮƵ using the then state-of-the-art Digital PDP-8i computer.

ݮƵ Archives

ݮƵ played an essential role

Prof. Leroy Cogger joined ݮƵ in 1971, hired specifically to work on ISIS-II science. Prof. Sandy Murphree started at the university as a postdoctoral fellow (later joining the faculty), whose job was to write and run software that reconstructed images out of ISIS II’s raw photometer data.

ݮƵ’s role was so essential that the space research group secured a then state-of-the-art Digital PDP-8i computer. The system, which took up most of a room on the sixth floor of the Science B Building, was capable of processing hundreds of kilobytes of data daily — considered remarkable in its day.

Murphree hired a 15-year-old high school student named James Gosling, who had knack for computing, to do odd jobs in the laboratory and work on the powerful new computer. Gosling would get a BSc in computer science at ݮƵ and go on to create Java, one of the world’s most widely used programming languages.

Anthony Lui, then a PhD student at ݮƵ, wrote his thesis based on ISIS-II data. Lui subsequently took a position at Johns Hopkins University and became a major global player in space physics, credited for discovering the “diffuse aurora,” a large luminous region that occurs over a broad range of geomagnetic latitudes.

Anger went on to become, in 1979, founder, owner and president of Calgary-based ITRES Research Limited, which designs and builds hyperspectral imaging sensors for use in aerial remote sensing. Cogger and Murphree retired from ݮƵ and became, along with Cogger’s PhD student Dr. Trond Trondsen, founding partners in 2003 of Keo Scientific, a Calgary firm that designs and builds imagers that support research on the aurora and other atmospheric phenomena.

Mission captured stunning auroral images

ISIS-II, passing over the polar region, captured the first-ever images of the aurora from above, confirming its then-theorized oval structure encircling the magnetic north pole.

“ISIS-II gave us this comprehensive, two-dimensional picture of what the aurora looked like, while at the same time making measurements of the plasma properties, parameters and processes that are related to producing the aurora,” Donovan says.

That enabled scientists for the first time to model and map daily conditions in the ionosphere, and link those conditions to auroral activities, says Greg Enno, manager of the ultraviolet (UV) imager project for the upcoming SMILE space mission. Enno worked on ISIS-II as a summer student during the last year of the mission.

“I don’t think anybody would have guessed back then how seminal the contributions from ISIS-II would be, that the mission would be foundational for a half-century to come,” says Dr. Dave Knudsen, PhD, professor and head of the Department of Physics and Astronomy.

ISIS-II’s success led to ݮƵ participating in several subsequent space missions. The university provided the scientific leadership for the UV auroral imagers on the Swedish (1986) and (1992) satellites, and the Russian-led (1996) auroral probe.

Professor Eric Donovan and SMILE-UVI Manager Greg Enno in front of an image of global auroral distribution as captured by the ISIS II satellite, which housed the first ݮƵ space instrument to view the aurora.

Eric Donovan and Greg Enno in front of an image of global auroral distribution as captured by the ISIS II satellite, which housed the first ݮƵ space instrument to view the aurora.

Riley Brandt, ݮƵ

ISIS-II left ongoing legacy

A research team led by Knudsen adapted the imaging technology developed by the space research group to design and build instruments to measure charged particles in the near-Earth environment.

ݮƵ is the only Canadian university that specializes in auroral imaging and charged particles measurement.

Knudsen is the scientific lead on three ݮƵ-built electric field instruments currently flying on the European Union’s triple-satellite , launched in 2013 to study the Earth’s electromagnetic field environment.

Four more instruments built at the university are flying on the 2013 Canadian hybrid satellite mission (now managed by the European Space Agency). The mission is gathering information to better understand the science of space weather, while verifying high-speed communications concepts through the use of advanced space technologies.

ݮƵ space physicists also are leading the design of the UV imager for the European Union and China’s , scheduled to launch in 2024.

The ݮƵ has participated in more than 20 national and international space missions since ISIS-II pioneered the way in 1971.

In addition, ݮƵ space physicists and engineers run 17 of the 22 ground-based observatories in NASA’s five-satellite , studying what causes explosive-storms in the aurora. They are also collaborating with international colleagues on TREx, a massive, ground-based network of optical and radio instruments dedicated to .

ISIS-II also led to the many graduate students and post-doctoral researchers who trained with ݮƵ space physicists on subsequent missions, and who are now working in research laboratories and industry in Canada and abroad.

Says Enno: “ISIS-II was not only a very successful mission that had a lot of impact at the time, it also paved the way for a very successful legacy that continues to this day.”

The in Ottawa plans to commemorate ISIS-II’s 50th anniversary on its website.