Short answers, pulled from the story.
Voyager 2 flew past Uranus in January 1986 to capture the first close-up images of its atmosphere. The probe found a planet that looked remarkably bland compared to Jupiter or Saturn with only ten distinct cloud features across the entire visible disk.
The southern collar is a narrow strip between minus 45 and minus 50 degrees latitude that forms the brightest feature known on Uranus. This collar likely represents dense methane clouds existing within a pressure range of 1.3 to 2 bar.
Astronomers detected their first dark spot on Uranus in 2006 using the Hubble Space Telescope and Keck Telescope. The feature measured roughly 1300 kilometres across latitude and 2700 kilometres along longitude.
Measurements taken from tracking cloud movements revealed retrograde winds blowing between minus 100 and minus 50 metres per second at the equator. Maximum speeds reached 150 to 200 metres per second at minus 40 degrees latitude in the south while northern hemisphere observations recorded maximums up to 240 metres per second near plus 50 degrees.
Uranus radiates hardly any excess heat compared to other giant planets despite receiving solar energy with its total power output in the far infrared spectrum equaling only about 0.03 times the absorbed solar energy. Scientists propose that a massive impact knocked Uranus over and expelled most primordial heat or that compositional layers block core heat from reaching the surface.