Mars mystery rock analysis shows unusual composition following sudden appearance

The NASA rover Opportunity sent back a couple of surprising images from Mars last week, both of which were taken with its Pancam, revealing the rather sudden appearance of a small rock. Researchers were surprised at the quick change, and though they offered a couple possible explanations, an investigation was kicked off to try and determine how it happened. Fast-forward through the weekend, and an analysis has offered a new surprise: the chemical composition is unlike anything previously analyzed on the Red Planet.

There is said to be a time span of a little under two weeks between the time the first picture — on the left — and the second picture were taken, the second including a small rock described as about the size of a jelly doughnut. A couple possibilities for the rock's appearance were put forth, among them being the accidental flinging of the rock by the rover due to a damaged front actuator or debris that landed there from nearby.

The researchers lucked out on the rock's positioning — it landed upside down, revealing an underbelly that hadn't been exposed to the surface in quite the long span of time, providing a new opportunity for study. Not wasting the chance, the rover Opportunity was sent to study the rock, and the information it sent back has expanded the mystery, showing a chemical composition not previously found on Mars.

According to the Mars Exploration Rover mission's lead scientist Steve Squyres, analysis has shown the rock contains "very high" levels of both magnesium and sulfur, as well as "twice as much manganese as has ever been seen in anything on Mars." He continued, "We're completely confused, we're having a wonderful time, everyone on the team is arguing and fighting."