Rings of Neptune 1846 when William Lassell, the discoverer of Neptune's largest moon, Triton, thought he had seen a ring around the planet. However, his claim was never confirmed and it is likely that it was an observational artifact. The first reliable detection of a ring was made in 1968 by stellar occultation, although that result would go unnoticed until 1977 when the rings of Uranus were discovered. Soon after the Uranus discovery, a team from Villanova University led by Harold J. Reitsema began searching for rings around Neptune. On 24 May 1981, they detected a dip in a star's brightness during one
The Tenth Planet of malevolent cyborgs that became a recurring adversary in later "Doctor Who" stories. The "tenth planet" in the title makes reference to a fictional lost planet in Earth's Solar System; at the time of production, the Solar System was generally held to consist of nine planets, prior to the redesignation of Pluto as a minor planet. "The Tenth Planet" is an incomplete "Doctor Who" serial – one of many serials that were affected by the BBC's policy of wiping archived programmes in the 1960s and 70s. Only three of the four episodes are currently held in the BBC archives; the