Curiosity Rover's 2023 Mars 'Jellyfish' Image Points to Cosmic Ray Hit

Q: Could this transient dark silhouette actually be a bizarre local dust phenomenon rather than a simple digital artifact from deep space radiation?

It is possible in principle, but the evidence strongly favors a camera or detector artifact over a real local dust event. Mars does produce brief atmospheric phenomena, especially dust devils and wind-lifted dust. Rovers and orbiters have photographed them many times. But those features usually have some visible structure tied to the ground, extend across more than a handful of pixels, or appear in multiple frames as they move. Here, the “jellyfish” shows up in only one low-resolution NavCam image, is only about 15 pixels across, and is absent in images of the same scene taken 13 seconds and 25 seconds earlier, as well as in a later image from the same camera. That timing is a problem for the dust explanation. A tiny, highly localized dust puff could be short-lived, but for it to create such a distinct dark silhouette in exactly one frame and leave no corroboration is less likely than a transient sensor event. Mars’s thin atmosphere also tends to make dust devils appear as broader columns or faint plumes, not a sharply bounded, tentacled shape. By contrast, Curiosity operates in a high-radiation environment, and similar one-frame anomalies have been seen before. A cosmic ray strike on the detector, or another electronic or processing glitch, can create dark residual shapes as well as bright ones. Without engineering logs, certainty is limited, but the balance of evidence points to something happening in the camera system, not in the Martian air just beyond it.

3 articles · Updated · ScienceAlert · Aug 28

A dark 'jellyfish-like' shadow in a Curiosity NavCam image from Aug. 20, 2023 appears to be a one-frame camera artifact, not an object on the Martian surface.
Two photos of the same scene taken 13 seconds and 25 seconds earlier show no trace of the shape, matching the brief, single-frame behavior expected from a cosmic ray striking the detector.
Mars leaves Curiosity unusually exposed to such hits because it lacks a global magnetic field and has an atmosphere with just 0.5% of Earth's mass.
NASA has long documented similar glitches in rover imagery—often bright spots or streaks, sometimes dark artifacts—though the report says only the imaging team could rule out other camera or processing errors definitively.