The planet Jupiter is famous for its size, it’s four largest moons, it’s Great Red Spot and it’s colourful system of cloudy stripes known as ‘belts’.  These features are all visible through small amateur telescopes, although the smallest telescopes can only make out the two darkest belts – the north and south equatorial belts.  Over the last year, however, one of these belts has gone missing.  Since Jupiter is a gas giant, it is composed mostly of a vastly deep and thick atmosphere, so that the features we see on it’s ‘surface’ are really just (mostly) stable weather features.  The Great Red Spot, for example, is a spectacular hurricane many times larger than the Earth, which has been blowing for over 400 years.  It is no surprise therefore that these features should change or vanish, but it is still a mystery as to why something which has been stable since the planet was discovered should vanish now.  More work for the planetary specialists!