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Peter Calamai
Science Reporter
Toronto, February 28, 2004 - Canada's bargain-basement space telescope, shot into orbit from a Russian cosmodrome last summer, is performing 10 times better than expected and astonishing scientists with its initial results.
The $10-million telescope has already recorded what our now middle-aged sun was like as a mere celestial teen by holding a similar and younger star in its cross-hairs for an unprecedented 29 days.
"There were solar super-flares and much more ultraviolet radiation. It was a violent time," said Slavek Rucinski, a University of Toronto astronomy professor who is analyzing the data from the teenaged, sun-like star in the constellation of Cetus, or the Whale.
The MOST telescope works like a super-sensitive light metre in space, measuring the level of brightness of distant objects instead of recording actual images. MOST is an acronym for Microvariability and Oscillation of STars.
The telescope's improved performance means it stands a good chance of making the first direct observation of worlds outside our own system, a quest that could start within weeks. The 100-plus extra-solar planets found so far have all been detected by indirect means such as weak gravity distortions.
The telescope should even be able to detect clouds if they exist in the atmosphere on the distant worlds, says Dimitar Sasselov, a member of the science team and Harvard University astronomy professor.
"For the first time we'll have a weather report from an extra-solar planet," Sasselov said.
As well, the MOST telescope has just wrapped up unequalled observations of a "big brother" of our sun, Procyon or the Little Dog star, the eighth-brightest star in the winter sky.
The Procyon results, now being reviewed by the journal Nature, will rock the astronomical community when published, predicts Jaymie Matthews, project chief scientist and astronomy professor at the University of British Columbia.
"We're going to be coming out with really big findings on a regular basis. No one has been able to look at other stars like this before," Matthews said.
While the tiny telescope was built in Vancouver, the whole spacecraft was assembled at the University of Toronto's Institute for Aerospace Studies, which also provides mission control. As well, the chief contractor is Dynacon Inc., a Toronto high-tech company specializing in automation and robotics.
"We're absolutely thrilled with the way it's going. It exceeded all our expectations," said Simon Grocott, MOST project manager at Dynacon.
Although no bigger than most backyard telescopes, MOST's 15-centimetre collecting mirror can detect variations in brilliance as small as one part per million.
That's like looking at a streetlamp a kilometre away and moving your eye a half-millimetre closer. The streetlamp would then appear brighter by one part per million.
The 10-times boost in performance resulted from software tweaking that improved a control system that can keep the telescope pointing at one star for up to two months. That pointing is now roughly 3,000 times better than anything achieved previously with such a small and light satellite - suitcase-sized and weighing a mere 50 kilograms.
By contrast, the Hubble space telescope weighs 11,000 kilograms, is the size of a tractor-trailer and cost $2.2 billion when launched in 1990. While Hubble can lock onto distant objects with greater accuracy than MOST, the demands on its time by astronomers are too great to let it focus on one star for weeks.
"We're into a new level of observing stars. We're going to record all the sounds of the stellar symphony," says UBC's Matthews.
Those "symphonic sounds" are generated by seismic waves inside our sun and other stars that cause the blazing surface to undulate, making the brightness vary by infinitesimally small amounts. Measuring these variations helps scientists determine the composition of the star, its age and how much longer it will burn.
The telescope, dubbed the "Humble" by some wags, was paid for by the Canadian Space Agency, which intends to fund other scientific microsatellites every second year.
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