A so-called supermoon will brighten the night sky tomorrow, though it might not be quite as super as some people believe. Supermoons occur when the moon's closest approach to the Earth — known as perigee — coincides with a full moon. The moon has an elliptical orbit with one side about 50,000 kilometres closer than the other. The perigee and the full moon occur within a minute of each other Saturday night (at about 11:35 p.m. ET), and the moon will seem as much as 14 per cent bigger and … [Read more...]