Multiple choice general knowledge science & technology The Great Red Spot, which has been seen since the 1600s, is thought to be what? An unidentified planet The largest sun spot An extremely large storm system wider than two Earths A new solar system related to Mars Reveal answer Fill a bubble to check yourself C Correct answer Explanation The Great Red Spot is a massive anticyclonic storm on Jupiter that has been observed for over 300 years. It is a high-pressure weather system wider than two Earths, not a planet, sunspot, or solar system.