Science & Technology

Space Cam: The Canadian Fleet

Both in this column and globally, organizations like NASA and the European Space Agency (ESA) tend to dominate the headlines. These organizations have large, expensive missions that are on the cutting edge of astronomy and space science. The Canadian Space Agency (CSA) does not have the same amount of money to throw around, unfortunately. However, Canadian scientists and engineers are still on the cutting edge of space exploration and scientific research. On the scientific side, an obvious example of this is the Sudbury Neutrino Observatory (not a CSA initiative), which recently earned Queen’s University’s astrophysicist Arthur McDonald the 2015 Nobel Prize for Physics. On the engineering side, the crowning glory of Canadian space expertise is the Canadarm, flown on 90 American space shuttle missions over 30 years.

The Canadarm was critical to a number of spectacular missions, like the securing of the space shuttle to MIR, the Russian space station, for a number of collaborations between the two nations. It was used to deploy the fantastically-successful Hubble Space Telescope, and then was instrumental in fixing a fatal optic flaw in the telescope that would have prevented any of its later illustrious career. The arm’s successor, Canadarm2, is located on the International Space Station (ISS) where it serves as the general-purpose manipulator of the station. The Canadarm2 was used during the assembly of the station. Now it is used for ongoing ship observation and maintenance, and securing unmanned resupply vehicles like SpaceX’s Dragon capsule. It can even inchworm around the station, gripping part of the station with its end while moving its shoulder to a new location.

Canada’s space presence extends far beyond just these two examples of exemplary achievement. Many large, well known missions—like the Hubble-succeeding James Webb Space Telescope and Curiosity Rover on Mars—have Canadian contributions. However, even leaving apart these collaborative efforts, the Canadian space fleet, while small, is strong.

MOST

The Microvariability and Oscillations of Stars (MOST) is Canada’s first space telescope. When it was launched in 2003, it was the smallest space telescope in the sky, a title it held until 2013. Despite its small size, MOST is able to perform useful scientific research; its small size means that there are fewer demands for it, and it can be used to study individual targets for up to 60 days at a time.

As the name would suggest, MOST is designed to carefully observe stars to sense very slight changes in their brightness. In particular, it can track sound waves within the star by observing the low frequency brightness variations they produce. This information closely correlates to the age of the star; as the star lives, it converts light hydrogen into comparatively heavy helium. The heavier helium propagates sound waves slower. This is the same principle by which inhaling lighter-than-air helium makes one’s voice more high-pitched. MOST’s sound wave data can be used to infer the amount of helium in the star, and therefore its age.

In 2010, the CSA terminated funding for MOST. Control of the telescope was transferred to Microsatellite Systems Canada Inc., the primary contractor for the program. They have been selling use of the satellite for a number of purposes. For instance, in addition to scientific research, the probe is now available for use as a test probe for novel attitude control systems that might go into future space craft.

The BRITE Constellation

The BRITE constellation is a group of six “nanosats,” as the CSA calls them. The classification is somewhat arbitrary, since these 20 cm-to-a-side cubes are larger than even the largest CubeSat “microsatilite” discussed in a recent “Space Cam.” This constellation carries on the work of MOST, observing stars for minute changes in their brightness.

The constellation is a collaborative effort of Canada, Poland, and Austria. All six satellites were designed by the University of Toronto Institute for Aerospace Studies, and five were built there. Three of the satellites are sensitive to red light, and the other half to blue. Unfortunately, one of the two Canadian-funded satellites, BRITE-Montreal, was lost after it apparently failed to separate from the launch vehicle. The second satellite, which was on the same flight, was released successfully. This example highlights the advantage of the CAS’s strategy of small—in the case of BRITE, tiny—satellites; the loss of any one satellite is frustrating, but not catastrophic to Canada’s scientific output.

NEOSSat

The Near-Earth Object Surveillance Satellite, or NEOSSat, is a small satellite operated by the University of Calgary. This telescope sits in low-Earth orbit, dedicated to tracking asteroids and man-made debris. Both of these are important topics of research, not just for scientific reasons but practical ones as well.

The asteroids being investigated by NEOSSat are interior-to-Earth asteroids. These are objects that are incredibly difficult to see using ground-based telescopes because they are visible during daylight or twilight, where the sun prevents or limits scientists’ ability to detect them. NEOSSat, being in space, does not suffer from this limitation, or other limitations like atmospheric noise and weather. As a result, although much smaller than the ground-based telescopes, it has a high potential to discover new bodies that might one day threaten to strike Earth.

The second half of NEOSSat’s mission is to track space debris and other satellites. This is an important task because, thanks to the high-speed nature of any object in orbit, even small pieces of debris can cause a massive amount of damage if they collide with a satellite. Satellite operators can use the data from NEOSSat, and a variety of other debris-seeking telescopes, to plan course changes away from possible impacts.

Cassiope

Cassiope is a two-part satellite, much like NEOSSat. The first part is the ePOP probe, which consists of 8 instruments designed to study space weather. In particular, these sensors study Earth’s ionosphere, the highest level of Earth’s atmosphere. This is an important region of research because solar weather can have a detrimental effect on various communication and satellite navigation technologies.

The second part of Cassiope is a proof-of-concept commercial payload called Cascade. Cascade is a high-volume data communication concept. Using just a small transmitter on a remote location like a seaborne ship or oil rig, a customer can transmit large quantities of data from the ground to Cascade at 1.2 gigabytes per second. Then, less than 90 minutes later, Cascade will pass within range of a ground station that can receive the collected data.

ePOP and Cascade are well-suited to work together in one satellite because they both require high-inclination (polar) orbits: ePOP to study the polar auroras that occur in the ionosphere and Cascade so that it can provide its services to all points on the globe.

This is just a sample of the great work that CSA does to advance scientific research and engineering. For instance, it does not include the human space program, which is currently getting ready for a new series of astronauts, or all the funding that it gives to other, smaller programs like supporting university teams in creating CubeSats. This is, and rightfully should be, a source of pride for Canadians, letting them strut their ingenuity and technical prowess.

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