NASA’s Dawn mission explored the giant asteroid Vesta, revealing its surface is pockmarked with craters and deep channels, or gullies, whose origins are not fully understood. A recent study published in The Planetary Science Journal provides new insights into these features, suggesting that impacts on Vesta may have triggered sudden and brief flows of water that carved the gullies.
Using lab equipment to mimic conditions on Vesta, scientists found that sodium chloride – table salt – is the critical component that keeps liquid brine flowing long enough to create specific surface features. Experiments showed that in Vesta-like conditions, pure water froze almost instantly, while briny liquids stayed fluid for at least an hour.
The researchers used a test chamber called DUSTIE to re-create Vesta’s environment after a meteoroid impact. By rapidly reducing air pressure around samples of liquid, they mimicked the environment around fluid that comes to the surface. The findings suggest that flows on Vesta could have etched gullies and other surface features similar to those on Earth.
The study contributes to a growing body of work using lab experiments to understand how liquids last on various worlds. According to project leader Jennifer Scully, “Not only do impacts trigger a flow of liquid on the surface, but the liquids are active long enough to create specific surface features.”
Source: https://phys.org/news/2024-12-lab-gullies-giant-asteroid-vesta.html