Usually we Earthlings are embarrassed by a planet named "Uranus". It is also the Penultimate Planet, before the Neptune - Plutino resonance marking the true end of the planetary system. Of itself, the planet is much less dynamic than the stormy Neptune which Event Horizon has immortalised. The planet was trending in Twitter yesterday, largely because it's visible to human eyesight and Islamicate-tech telescoping for once. (The Muslims never saw it. As usual for them: so close yet so far.) But there was more news.
The Herschel Space Observatory rediscovered Uranus' five moons in the infrared. Bill Herschel had discovered infrared, and moons Titania and Oberon, in the first place so it all well lives up to the man's legacy. The rediscovery wasn't redundant, as you might think; this showed the moons were hotter than they "should" be.
Really what this has done is to constrain the five moons' capacity for heat retention. That is: with their known density, we have a hint to their composition. The answer is: Plutolike. They're rocky, with a layer of ice as ice is defined in the outer system.
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