Written by Margaret Dane, Ph.D. Students at Purdue University
Last week, NASA’s Mangal 2020 Rover continued his journey under the ‘Witch Hazel Hill’ on the Jazero Crater Rim. The rover stopped with a range visible from a border, which appears from light and dark rock outcrops (also known as contact) on a site, the team has called ‘Port Anson’. In addition to this contact, the rover has suffered a variety of clean -cotton rocks, which can be generated from elsewhere and is taken to their current location, also known as a float.
There is an observation painted above called ‘Skull Hill’, which is taken by the Rover’s Mastcam-Z Instrument. This float rock is uniquely unlike its dark tone and surrounding light-tond outcrops with its dark tone and angular surface, and it has some pits in the rock. If you look closely, you can also spot shells inside the surrounding resolith! For more information about these clean features, see the recent blog post of Alex Jones: https://science.nasa.gov/blog/blog/blog/blog/shocking-spherules/. Pits on the skull hill can be through the erosion of rocks from the rock or scoring from the wind. We have found some of these dark-tond floats in the Port Enson region, and the team is working better to understand where these rocks have come from and how they reached here.
The dark color of the skull hill is reminiscent of the meteorites found in the Gayle Crater by Curiosity Rover: https://www.jpl.nasa.gov/news/curiosity-mars-squars-sks-sd–looking-metorite/. Chemical composition is an important factor in identifying a meteorite, and the meteorites of GAIL contain significant amounts of iron and nickel. However, recent analysis of supercam data from nearby rocks suggests an composition inconsistent with a meteorite origin.
Alternatively, the ‘skull hill’ can be a fiery rock that is erased from a nearby outflow or an effect can be taken out of the pit. On Earth and Mars, iron and magnesium are some of the main contributors of igneous rocks, which are formed by the cooling of magma or lava. These rocks may include dark minerals such as olivin, pyroxine, amphil and biotite. Fortunately for us, the rover has devices that can measure the chemical composition of rocks on Mars. Understanding the composition of these dark -colored toned floats will help the team to explain the origin of this unique rock!
