{"id":18435,"date":"2018-07-17T19:37:40","date_gmt":"2018-07-17T11:37:40","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/discoveries-boost-jupiters-retinue-to-79-moons-including-a-wrong-way-oddball\/"},"modified":"2018-07-17T19:37:40","modified_gmt":"2018-07-17T11:37:40","slug":"discoveries-boost-jupiters-retinue-to-79-moons-including-a-wrong-way-oddball","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/discoveries-boost-jupiters-retinue-to-79-moons-including-a-wrong-way-oddball\/","title":{"rendered":"Discoveries boost Jupiter\u2019s retinue to 79 moons \u2014 including a wrong-way oddball"},"content":{"rendered":"
\"Jovian
The oddball Jovian moon, known as Valetudo, crosses the orbits of moons that move in the opposite direction. Click on the image for a larger version. (Carnegie Institution of Science \/ Roberto Molar Candanosa)<\/figcaption><\/figure>\n

Astronomers searching for signs of a hypothetical \u201cPlanet Nine\u201d have instead come up with 12 new moons of Jupiter, including one that hints at a cosmic crack-up.<\/p>\n

The discoveries were made more than a year ago, and the orbits of two of the moons were confirmed soon after they were found. It took much longer for the other 10 to have their orbits verified.<\/p>\n

\u201cIt takes several observations to confirm an object actually orbits around Jupiter<\/span>,\u201d Gareth Williams of the International Astronomical Union\u2019s Minor Planet Center explained in a news release. \u201cSo, the whole process took a year.\u201d<\/p>\n

\"Moon
The Magellan telescope in Chile captured these recovery images of the oddball Jovian moon, known as Valetudo, in May. The moon can be seen moving relative to the background of distant stars. (Carnegie Science \/ Las Campanas Observatory)<\/figcaption><\/figure>\n

The Minor Planet Center published the remaining 10-pack\u2019s orbital parameters today, marking their formal acceptance as Jovian moons. That brings Jupiter\u2019s total tally to 79 moons, easily besting runner-up Saturn\u2019s count of 62.<\/p>\n

None of the dozen moons is more than a couple of miles across. Two of them have relatively close-in orbits, going in the same direction as Jupiter\u2019s spin. Nine of them orbit farther out, in a retrograde direction \u2014 that is, opposite to the direction of the giant planet\u2019s rotation.<\/p>\n

\u201cOur other discovery is a real oddball and has an orbit like no other known Jovian moon,\u201d said Scott Sheppard of the Carnegie Institution for Science, who led the discovery team. \u201cIt\u2019s also likely Jupiter\u2019s smallest known moon, being less than 1 kilometer in diameter.\u201d<\/p>\n

The oddball moon crosses the orbits of the outer retrograde moons.<\/p>\n

\u201cThis is an unstable situation,\u201d said Sheppard. \u201cHead-on collisions would quickly break apart and grind the objects down to dust.\u201d<\/p>\n

The oddball could be the last remaining remnant of a once-larger moon that gave rise to the retrograde retinue during previous smash-ups. The circumstances of the moons\u2019 orbits lend further support to the view that they were formed long after Saturn and its larger moons coalesced from a primordial cloud of gas and dust.<\/p>\n