"Spotting nearly flawless spheres on the Martian surface is a rare occurrence for a rover. More than twenty years ago, NASA’s Opportunity rover made headlines after finding hematite-rich spherules (nicknamed “blueberries”) near its landing site in Meridiani Planum.
Now, the Perseverance rover has come across a similar surprise: small spherical formations, some embedded in bedrock and others scattered loosely across an area informally known as “Witch Hazel Hill.”
In an earlier update, the team highlighted Perseverance’s close-up study of a spherule-bearing rock formation at a site called “Hare Bay,” where a core sample was later collected. After adding the “Bell Island” core to its collection, the science team turned its attention to the loose spherules in the surrounding terrain, which seem to have weathered out of nearby rock layers.
Despite their superficial similarity to Opportunity’s “blueberries,” the spherules at “Rowsell Hill” have a very different composition and likely origin.
In an earlier update, the team highlighted Perseverance’s close-up study of a spherule-bearing rock formation at a site called “Hare Bay,” where a core sample was later collected. After adding the “Bell Island” core to its collection, the science team turned its attention to the loose spherules in the surrounding terrain, which seem to have weathered out of nearby rock layers.
In Meridiani Planum, the spherules were composed of the mineral hematite and were interpreted to have formed in groundwater-saturated sediments in Mars’ distant past.
By comparison, the spherules in “Rowsell Hill” have a basaltic composition and likely formed during a meteoroid impact or volcanic eruption. When a meteoroid crashes into the surface of Mars, it can melt rock and send molten droplets spraying into the air. Those droplets can then rapidly cool, solidifying into spherules that rain down on the surrounding area. Alternatively, the spherules may have formed from molten lava during a volcanic eruption.
If they instead formed during a volcanic eruption, they could preserve clues about past volcanism in the region around Jezero crater."
By comparison, the spherules in “Rowsell Hill” have a basaltic composition and likely formed during a meteoroid impact or volcanic eruption. When a meteoroid crashes into the surface of Mars, it can melt rock and send molten droplets spraying into the air. Those droplets can then rapidly cool, solidifying into spherules that rain down on the surrounding area. Alternatively, the spherules may have formed from molten lava during a volcanic eruption.
If they instead formed during a volcanic eruption, they could preserve clues about past volcanism in the region around Jezero crater."
SciTechDaily
Q: Why the Surprise on Witch Hazel Hill and elsewhere? It's a PLANET---of course it has volcanic activity.
