NASA's Curiosity rover captured a mysterious dark silhouette resembling a 'jellyfish' with a rounded head and hanging filaments on the horizon of the Gale crater on Mars. ^[1] A dark figure resembling a jellyfish appeared in a photograph taken by the NASA Curiosity rover on Mars on August 20, 2023, in the Gale crater. ^[2] Scientists hypothesize that the image anomaly was caused by a cosmic ray impacting the camera sensor. ^[3] The figure was not visible in other images taken by the Curiosity rover 13 and 25 seconds before or 78 minutes after the original shot. ^[4] Comparative analysis revealed that two photos taken 13 and 25 seconds before the anomaly appeared showed no such figure, and a photo taken 78 minutes later also lacked the silhouette. ^[5] The image was taken by the rover's right navigation camera on August 20, 2023, and remained unnoticed until it went viral on social media in August 2026. ^[6] The NASA Jet Propulsion Laboratory explained in 2014 that cosmic rays can cause bright spots or patterns in Curiosity images due to Mars's lack of a global magnetic field. ^[7] Science Alert noted that Mars lacks a global magnetic field and has an atmosphere only 0.5% the mass of Earth's, leaving the Curiosity instruments more exposed to high-energy particles from space. ^[8]