|Discovered by||Scott S. Sheppard|
|S/2003 J 3|
|Orbital characteristics |
It was discovered by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2003. The moon was lost following its discovery in 2003. It was recovered in 2017 and given its permanent designation that year.
It was named in 2019 after Eupheme, the ancient Greek spirit of words of good omen, praise, acclaims, shouts of triumph, and applause, the daughter of Hephaestus and Aglaea and granddaughter of Zeus. The name was suggested by Twitter user Lunartic (@iamalunartic) in a naming contest held by the Carnegie Institute who concurrently helped in naming another Jovian moon Philophrosyne.
Eupheme orbits Jupiter at an average distance of 19,622 Mm in 561.518 days, at an inclination of 146° to the ecliptic (146° to Jupiter's equator), in a retrograde direction and with an eccentricity of 0.2507. It belongs to the Ananke group, retrograde irregular moons that orbit Jupiter between 19.3 and 22.7 Gm, at inclinations of roughly 150°.
We likely have all of the lost moons in our new observations from 2017, but to link them back to the remaining lost 2003 objects requires more observations a year later to confirm the linkages, which will not happen until early 2018. ... There are likely a few more new moons as well in our 2017 observations, but we need to reobserve them in 2018 to determine which of the discoveries are new and which are lost 2003 moons.