Ganymede is not only the largest satellite of Jupiter and the biggest moonlight in the Solar System , but it is the only moon with its own magnetic field and is also tidally locked , meaning it always shows Jupiter the same boldness just like our Moon does to us . On the far side of Ganymede , there is evidence of a colossal volcanic crater – grounds of an impact that change the remote world incessantly .
It all started about 4 billion years ago . An asteroid – about 20 time larger than the distance rock that killed the dinosaurs , with a radius of 150 kilometers ( 93 miles ) – create a transitory crater with a r of at least 700 kilometer ( 435 miles ) , braggart enough to contain one - one-sixth of the United States . But that is not all that it did .
This encroachment would affect the interior anatomical structure of Ganymede importantly
Artist’s impression of the impact on Ganymede and the moon’s successive realignment.Image Credit: HIRATA Naoyuki
Ganymede is believe to have a liquid ocean under a thick shell of chicken feed and rock , much thicker than fellow Jovian moonlight Europa . The impact might have been need in the formation of this ocean , and it was so dramatic that changed the revolving bloc of Ganymede . Over fourth dimension , the singular scrape of this impingement ended up facing aside from Jupiter .
“ This shock would affect the inner complex body part of Ganymede importantly , because the size of the transient crater reach 25 percent of the size of Ganymede . Also , it is known that the reorientation can itself cause significant warming in the interior due to tidal dissipation . Those would be potentially affiliate with the origin of Ganymede ’s interior sea . I plan to analyze this issue as my succeeding research , ” report writer and planetologistNaoyuki Hirata , Assistant Professor in the Department of Planetology at Kobe University , told IFLScience .
The pretending make by Hirata are challenging . It does n’t seem to matter where the wallop might have occurred : as long as it was that sizable , the moonlight will have ended up reorienting itself in the direction we find it today .
Ganymede is covered in structures known as furrows (right). They form concentric circles around one specific spot (left, red cross). This led researchers in the 1980s to conclude that they formed from a major impact.Image Credit: HIRATA Naoyuki
There are many unknowns about Ganymede , so the research allow some potential penetration . But without more observations , it will be very difficult to confirm this and next work . fortunately , we do not have to wait too long – the European Space Agency’sJUICE missionwill get to Jupiter in 2031 to study Ganymede , Europa , and Callisto . In 2034 , it will become the first ever space vehicle to orbit a planet ’s moonlight as it begins its in - depth observational movement of Ganymede .
“ I am really looking forth to the data from the JUICE . The Voyager 1/2 and Galileo ballistic capsule have observed Ganymede , however , many areas of Ganymede still have not been imaged with sufficient resolution , ” Hirata told IFLScience . “ The current accuracy of the gravity and topography measurements of Ganymede are none or very deficient . Future exploration would reveal a remnant of topographical profiles or gravity anomalies associated with the furrow - form impact and the reorientation of Ganymede , which would supply insights into this gargantuan wallop and Ganymede ’s early chronicle . ”
A paper discuss this work is published in the journalScientific Reports .
