Editing Janus (moon) (section)

==History==

=== Discovery ===
Janus was identified by [[Audouin Dollfus]] on 15 December 1966{{sfn|IAUC 1987}} and given the temporary designation '''{{nowrap|S/1966 S 2}}'''. Previously, {{ill|Jean Texereau|fr}} had photographed Janus on 29 October 1966 without realising it. On 18 December, Richard Walker observed an object in the same orbit as Janus, but whose position could not be reconciled with the previous observations. Twelve years later, in October 1978, Stephen M. Larson and John W. Fountain realised that the 1966 observations were best explained by two distinct objects (Janus and Epimetheus) sharing very similar orbits,{{sfn|Fountain|Larson|1978}} Walker is now credited with the discovery of [[Epimetheus (moon)|Epimetheus]].{{sfn|IAUC 1991}} ''[[Voyager 1]]'' confirmed this orbital configuration in 1980.{{sfn|Solar System, NASA: Janus}}

===Observational history===
Janus was observed on subsequent occasions and given different [[provisional designation in astronomy|provisional designations]]. ''[[Pioneer 11]]''{{'s}} three energetic-particle detectors detected its "shadow" when the probe flew by Saturn on 1 September 1979 ('''{{nowrap|S/1979 S 2}}''').{{sfn|IAUC 3417}}<!--- [[Tom Gehrels]] and [[James A. van Allen]] ---> Janus was observed by Dan Pascu on 19 February 1980 ('''{{nowrap|S/1980 S 1}}'''),{{sfn|IAUC 3454}} and then by John W. Fountain, Stephen M. Larson, [[Harold J. Reitsema]] and Bradford A. Smith on 23 February 1980 ('''{{nowrap|S/1980 S 2}}''').{{sfn|IAUC 3456}}

=== Name ===
Janus is named after the two-faced [[Roman mythology|Roman]] god [[Janus (mythology)|Janus]]. Although the name was informally proposed soon after the initial 1966 discovery,{{sfn|IAUC 1995}} it was not officially adopted until 1983,{{efn|name=mythology}} when [[Epimetheus (moon)|Epimetheus]] was also named.