Uranus is known as the planet lying on its side with a vertical ring. The ring system was discovered because it sometimes occults (blocks the light) from stars behind it. It is dim in visible light and not easy to observe, but we can see its form in infrared images produced by a space telescope or a large ground based telescope. This picture is an image taken with the near infrared camera CIAO (Coronagraphic Imager with Adaptive Optics) mounted on the Subaru Telescope. Uranus with its methane atmosphere, its ring and its moons Ariel and Miranda appear clearly. This camera is no longer in use, but we are conducting observations with its successor, the high contrast camera HiCIAO (High Contrast Instrument for the Subaru Next Generation Adaptive Optics.) It is yielding direct observations not of Solar System planets, but of protoplanetary disks and extra-solar planets.

Author: Nobuhiko Kusakabe (Extra-Solar Planet Office)