NASA researchers reveled the secret of reddish color spot of Jupiter. They said the ruddy color of Jupiter's famous Great Red Spot is likely a product of simple chemicals being broken apart by sunlight in the planet's upper atmosphere.
The results, which is based on a combination of data from the December 2000 Jupiter flyby of NASA's Cassini spacecraft and laboratory experiments, contradicted the other leading theory for the origin of the spot's striking colour that the reddish chemicals come from beneath Jupiter's clouds.
Researchers blasted ammonia and acetylene gases, chemicals known to exist on Jupiter with ultraviolet light, to simulate the sun's effects on these materials at the extreme heights of clouds in the Great Red Spot in the lab. The simulation produced a reddish material that "nicely matched" a model of the Great Red Spot. The red-colored material was confined to the uppermost reaches of the giant cyclone-like feature, says a statement issued by the NASA researchers on Tuesday.
Kevin Baines, a Cassini team scientist based at NASA's Jet Propulsion Laboratory said, "Our models suggest most of the Great Red Spot is actually pretty bland in colour, beneath the upper cloud layer of reddish material, Under the reddish 'sunburn' the clouds are probably whitish or greyish."
He said that a coloring agent confined to the top of the clouds would be inconsistent with the competing theory, which states that the spot's red color is due to up-welling chemicals formed deep beneath the visible cloud layers.
He also added, if red material were being transported from below, it should be present at other altitudes as well, which would make the red spot redder.
Baines said, "The Great Red Spot is extremely tall, it reaches much higher altitudes than clouds elsewhere on Jupiter."
As per the opinion researchers, the spot's winds transport ammonia ice particles higher into the atmosphere than usual, where they are exposed to much more of the sun's ultraviolet light.
Moreover, the vortex nature of the spot confines particles, preventing them from escaping, which causes the redness of the spot's cloud tops to increase beyond what might otherwise be expected.