Unlike its solar-powered siblings, Spirit and Opportunity, Curiosity has a nuclear battery that lets it run at any time of day. The rover’s Mars Hand Lens Imager (MAHLI) camera is fitted with four white and two ultraviolet LEDs to help it explore once the sun goes down. In addition to throwing killer Martian raves, the ultraviolet flashlight allowed the rover to look for fluorescent minerals in a rock nicknamed “Sayunei” (above).
Very little is currently known about the fluorescent properties of Martian soil and the UV LEDs are mostly being used for exploratory purposes for the time being. Tests conducted on Earth (.pdf) using Martian meteorites showed that phosphate minerals such as whitlockite glowed under UV illumination. If the science team sees anything shining green, yellow, orange, or red under the UV lights, it could indicate interesting mineralogy that might go undetected using normal white lights or sunlight.
Curiosity’s MAHLI camera also used its white light LEDs to take a closer look at “Sayunei” (below). The rover scuffed the rock with its wheel to clear it of dust and then examined it up close. The information may come in handy when Curiosity drills.
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