A 15-year-old from Quebec who demonstrated that Jupiter is able to cast a perceptible shadow similar to shadows cast by the sun, the moon, Venus and the Milky Way has won the Canada-Wide Science Fair.

Laurent V. Joli-Cœur of Collège Jean-de-Brébeuf in Montreal won the best project award, which comes with $10,000, donated by Research in Motion, and another $11,000 in prizes, including an entrance scholarship to Western University in London, Ont.

For his astronomy experiment, Joli-Coeur built a sundial-like instrument that could capture the astral shadow cast by Jupiter and took time exposure photographs of the slight shift in the planet's shadow. By rotating the rod, or gnomon, used to capture the shadow and also pointing it away from Jupiter, he was able to verify that the shadow came from no other source than Jupiter.

The project caught the eye last year of Discover magazine blogger Phil Plait, who gave kudos to the young amateur astronomer on his blog, Bad Astronomy.

Joli-Coeur himself has his own blog, called Young Astronomer, in which he posts photographs he has taken through his telescopes.

The science fair, which wrapped up Saturday in Charlottetown, attracted more than 500 participants from across the country.