Ceres, the largest asteroid in our solar system, has long been a source of fascination for astronomers and planetary scientists. Recent discoveries reveal that this icy dwarf planet may have once been an ancient ocean world, shedding new light on the origins and evolution of our solar system.
From Craters to Crust
Ceres, its heavily battered and dimpled surface marked by so many impact craters, has long puzzled scientists. It was earlier thought that Ceres is a dry body, with an ice content of less than 30%.
That goes against the conventional wisdom, but some researchers from Purdue University and NASA’s Jet Propulsion Lab are saying otherwise. And using new computer modeling techniques, they’ve found that even more — as much as 90% of the surface layer — could be ice. It is a conclusion that runs counter to the generally accepted view that, because it has craters it could not have been a very icy body.
Unveiling Ceres’ Icy Past
Ceres was once a rather wet place, at least underground, suggesting either that the dwarf planet formed near icy bodies in the young solar system and/or it brought water to itself via many small impacts. But whereas Europa’s ice crust overlies an ocean of liquid water, Ceres’ ancient ocean was ‘dirty’ and ‘muddy’, laced with rocky debris.
The muddy ocean eventually was covered with ice, forming a relatively thin crust which contained about 1-2% less rocky material. The researchers used computer simulations to conclude that this ice crust is strong enough to keep shallow, deformed craters intact even after 4 billion years — much longer than such craters would last on the gas-rich asteroid Vesta or Europa, one of Jupiter’s moons.
The find indicates that Ceres is much icier than already suspected —its surface may be up to 90% ice. The fact that ice becomes less dominant with increasing depth is an important reason why the craters have survived for so long on Ceres.
Conclusion
The discovery that Ceres is an ocean world has important implications for the history of our solar system. Not only is Ceres the most accessible icy world in the universe, it also promises to offer some tantalizing secrets of its own with future spacecraft missions. As we continue to unravel Ceres’ mysteries, they offer insights into the creation of life and the environment necessary for future worlds that might be similar!
