THE Dark Side of Jupiter last night contrived with low cloud and bright lights to deprive Hong Kong astronomers of a chance to see comets smashing into the planet. Although astronomers in the territory saw more of the galactic fireworks from Shoemaker-Levy 9 on television sets than through their telescopes, 10-year-old Wong Ching-hing said he had a night he would never forget. Ching-hing was among the first of hundreds of people waiting outside the Museum of Arts in Tsim Sha Tsui to watch Jupiter through a telescope provided by the Space Museum. Having waited 90 minutes, Ching-hing was thrilled, even though he was allowed to look through the telescope for only about 30 seconds. ''I saw Jupiter and some small stars [the moons], I am very happy,'' he said. Two telescopes will be placed outside the Museum of Arts from 7.30 pm to 10 pm every night until 25 July. Meanwhile, astronomers overseas said yesterday the spectacular smash of a comet chunk into Jupiter indicated other fragments were likely to hold together rather than disintegrate immediately in the atmosphere of the giant planet. This should produce even more dramatic impacts as the rest of the comet slams into Jupiter's gaseous atmosphere over the coming week. The first and possibly smallest fragment ploughed into Jupiter on Saturday night, with astronomers from around the world gathered at the observatory in the small South African sheep town of Sutherland for a ringside view. ''This was one of the very smallest fragments,'' said one astronomer. ''So if there is any justice, the ones that look big ought to produce something really spectacular.'' Fragment A, one of the 21 pieces of the comet, smashed into Jupiter's atmosphere at over 200,000 km/h and sent a fireball from the explosion 1,000 km above the surface.