A once-in-a-lifetime holiday treat is on track to delight sky watchers this month on the Winter Solstice. Jupiter and Saturn are moving closer to each other, culminating in what is called ‘The Great Conjunction’ on December 21. The two planets will be so close they will look like one bright star. On that day, scientists advise sky watchers to look above the horizon in the southwest sky just after sunset and to do it quickly, as the planets will set shortly after sunset. Watchers don’t even need a telescope; experts say the planets will be spectacular viewed by the naked eye.