Canada's stellar microsatellite

MOST is the size of a suitcase and a fraction of the cost of similar satellites

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Many Canadians know that the former Soviet Union and the U.S. were the first to send satellites into space, but few realize that Canada came third in the space race. Forty-six years after the launch of Alouette 1, even fewer are aware that another Canadian satellite has been making breakthroughs and headlines in stellar research.

Nicknamed the "Humble Space Telescope," the Microvariability and Oscillations of Stars Microsatellite has been observing the stars since 2003.

On Friday, MOST's mission scientist and University of British Columbia astronomy associate professor Dr. Jaymie Matthews spoke at the University of Calgary's department of physics and astronomy weekly colloquium. His presentation, "The MOST Microsat: A suitcase full of Stars and Exoplanets," outlined the significance and achievements of the project.

"MOST is Canada's first space telescope," said Matthews. "It was the first all-Canadian science satellite in over 30 years. It represents a resurgence in Canadian space science and a return to the pre-eminence that we had in the beginning of the space age [with] the legacy of Alouette 1."

Traditional stellar research had relied on ground-based telescopes and observatories which contended with the distortion of the Earth's atmosphere and limited observation time due to the night and day cycle. MOST overcame these issues with its polar orbit placement above where night meets day. Targeted stars can be observed for two months using MOST's optical telescope, which measures the tiny surface vibrations in a star by observing changes in its brightness to a level of one part per million. To put this in perspective, Matthews used the analogy of New York City's Empire State Building with all its office lights turned on at night. He said to dim the lighting for one part per million you would need to lower one blind by three centimetres.

With this precision, MOST is able to provide information about surface spot activity, internal composition and the age of stars similar to our sun. All of these capabilities are stuffed into a package no bigger than a suitcase. With a price tag of only $10 million, MOST's massive achieve-ments contrast with its diminutive size and small budget.

"We're the Zellers of space telescopes," quipped Matthews. "A normal mission with our kind of science goals and capabilities would have a price tag of at least $250 million."

MOST was originally intended to last for one year and map a handful of stars. Five years and 1,400 stars later, it is projected to be useful until 2012.