The moons of Uranus


There are 27 known natural satellites orbiting Uranus. We can see 4 of the largest in this photo which has been deliberately overexposed to make them stand out better with the small telescope I used. Starting from the top and clockwise: Oberon (diameter 1,500 km), Titania (diam: 1,600 km), Umbriel (diam: 1,200 km) and to the left of Uranus (lost in its glare), Ariel (diam: 1,200 km). Uranus was at the time of this photo 2.9 billion km from us, not exactly next door …

Technical details:

Telescope: SkyWatcher Esprit 120mm f/7  (focal length: 840 mm)
Camera: ZWO ASI 071 MC
Exposure: 1 single 4-minute frame
Place: Laval, Qc