Medusae Fossae Formation Still provides Mysteries

The Mars Express probe has recently sent back deep-penetrating radar data of the Medusae Fossae Formation near the equator of Mars. The formation is near the divide between highlands and lowlands and has often been called a "stealth" spot due to the fact that it has absorbed other forms forms of radar at higher wavelengths. The spot intrigues scientists because it lacks much cratering, indicating that it may be one of the youngest geologic spots on the planet. The new data is consistent with a fluffy substance like dust, in a lyer 1.4 miles thick. However it seems unlikely that dust would be so thick, offering the possibility of volcanic ash. The electrical properties of the formation indicate a substance much more like water ice. In all, the new information raises as many questions as it has solved and some of the scientists involved speculate that unless new ways to analyze the spot can be created, we may never know what the formation is made of until we actually go there.

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