One of the weirdest of the solar system ’s moons is Iapetus . This is a intermediate - sized ( 1,471 km ( 914 statute mile ) satellite of Saturn , revolve about 3,561,300 km ( 2,213,000 miles ) from the satellite . Seen from the control surface of Iapetus , Saturn looms about four times enceinte than a full moonlight in Earth ’s sky .
Ever since its find by Cassini in 1671 , something seemed strange about Iapetus . For one thing , it commute brightness as it orbited Saturn . The only explanation anyone could think of was that , for some unknown ground , Iapetus is brighter on one side than the other . And that turned out to be fairly close to the Sojourner Truth .
In fact , one side is almost as dark as coal while the other is almost as white as blow or ice . When the saturnine side is facing Earth , the satellite appear dim . When the unclouded side faces us , Iapetus brightens up .
The first space probe to fly by Iapetus revealed a moon that looked almost exactly like the traditional yin - yang symbol . An S - work curve separated the satellite into two distinct zone , one iniquity and one light . Why this should be so is really something of a mystery , for which there are several potential answers . One is that dark material shed by the outer moon , Phoebe , helix in and is sweep up by the run hemisphere of Iapetus . Another is that the dark material might have been deposited by volcano - same eruptions of hydrocarbons .
But even this two - toned paint caper is n’t the weird matter about Iapetus . That ’s reserved for its equatorial mountain range . There ’s nothing else like it in the solar system . Running almost all around the satellite like a bash , reach makes Iapetus attend as though someone slammed the two halves the moon together and the glue oozed out . Some uranologist think the rooftree was formed at a fourth dimension in the aloof past when Iapetus splay much quicker .
Another possibility is that the reach was make by the flop of a ring . A similar ideawas of late proposed by William B. McKinnon of Washington University and Andrew Dombard of the University of Illinois Chicago . Their idea is that Iapetus once had a satellite of its own . As it float near to Iapetus , the moon was tear apart by tidal forces . The detritus formed a ring that eventually fell onto the lunation ’s equator , make up the mickle mountain chain as it did so . “ guess all of these subatomic particle add up down horizontally across the equatorial surface at about 400 meters per second , ” enunciate McKinnon , “ The speed of a rifle slug , one after the other , like frozen baseballs . ”
While a ikon of the apocalyptic bloodline of Iapetus ’ ring is still in the future , I imagined what its ancient satellite might look like , share the sky with Saturn , and what it might be like to see two ringed worlds in the sky at the same metre . I also wondered what the lot grasp might take care like to explorers clambering around among its tough foothills , its peaks stretching railroad - straight over the horizon . The results are the accompanying illustration here ( chatter any to enlarge ) .
Ron Miller is a skill artist . you could see more of his workon his website .
moonsScienceSpace
Daily Newsletter
Get the best technical school , skill , and culture news in your inbox daily .
News from the future tense , delivered to your present .
You May Also Like
