English: MEDA's Radiation and Dust Sensor

This dust and radiation sensor is part of the Mars Environmental Dynamics Analyzer suite and is mounted on the deck of the Perseverance rover. It measures how much sunlight is scattered by dust in the Mars atmosphere. On the top horizontal surface, there are eight photodiodes, which convert light into electricity. Each photodiode measures a different wavelength of light in the atmosphere above the rover. Eight additional photodiodes measure how dust scatters the light closer to the horizon. It also includes a camera that looks at the sky, called SkyCam, and will frequently take photos of the sky to study the atmospheric opacity and the clouds above Mars.

The small black tube that protrudes from the rover deck to the left of the Radiation and Dust Sensor is a chimney that gives Pressure Sensor inside the rover body access to the atmosphere.