Juno probe completes historic Great Red Spot flyby
Juno chalked another one up for the history books, as it completed the first close flyby of Jupiter's Great Red Spot. NASA today confirmed that the unmanned probe passed within 5,600 mi (9,000 km) of the giant storm at 7:06 pm PDT on June 10 during its sixth science orbit of the planet. The spacecraft's science instruments and JunoCam imager beamed data back to Earth during the encounter, and the space agency says raw images will be released over the next few days.
Yesterday's flyby is the closest that any spacecraft has ever approached the Red Spot, which is a cyclonic storm 10,000 mi (16,000 km) wide in the upper atmosphere of Jupiter, that has been raging for perhaps more than 350 years. First tentatively identified by the English scientist Robert Hooke in 1664, it's been under observation by earthbound astronomers since 1830.
Though the storm has been blowing since the Renaissance, it's shown signs of shrinking in recent years. This is of particular interest to scientists, not only because of what it can tell them about the structure of the Jovian atmosphere, but also the insights it can provide about climate in general.
NASA says that Juno reached its closest point to Jupiter at 6:55 pm when it came within 2,200 mi (3,500 km) of the cloud tops, reaching the Red Spot 11 minutes and 33 seconds later.
Launched on August 5, 2011, the solar-powered Juno probe arrived at Jupiter on July 4, 2016 when it took up a highly eccentric 53.4-day orbit that periodically brings it within 2,100 mi (3,400 km) of the cloud tops. It is scheduled to make its next close pass to Jupiter on September 1. By the time it completes its 37th orbit in 2018, it will have suffered so much damage from Jupiter's radiation belts that its functions will be impaired and NASA will dispose of it by a controlled deorbit into the Jovian atmosphere.
"For generations people from all over the world and all walks of life have marvelled over the Great Red Spot," says Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio. "Now we are finally going to see what this storm looks like up close and personal."