There was excitement for South African amateur astronomer Clyde Foster this week when NASA’s Juno team referred to a discovery he made as “Clyde’s Spot”.
Foster is a retired chemical engineer who has become a passionate amateur astronomer specialising in planetary imaging.
In the early hours of Sunday, 31 May 2020, he was imaging Jupiter through his telescope when he noticed a new spot on the planet’s surface. The new spot was “bright in Methane wavelengths”, Foster said.
Just 10 hours earlier, the spot had not been there. Renowned astronomy photographer Andy Casely had captured images of Jupiter from Australia which did not show the spot.
Foster explained that “outbreaks” like this are relatively rare in the particular region of Jupiter where he found it.
“It is a regular occurrence in Jupiter’s North and South Equatorial belts, but substantially rarer in this location, the South Temperate region,” he said.
It’s for this reason that his discovery generated “quite a bit of interest” in the professional-amateur planetary science community.
Smile for the JunoCam
As luck would have it, NASA’s Juno spacecraft was set to perform its 27th close flyby of Jupiter on 2 June, just days after Foster’s discovery.
Even luckier was that Juno happened to be flying by close enough to Clyde’s Spot to get a detailed look at the phenomenon.
“The spacecraft can only image a relatively thin slice of Jupiter’s cloud tops during each pass,” the Juno team explained.
“Although Juno would not be travelling directly over the outbreak, the track was close enough that the mission team determined the spacecraft would obtain a detailed view of the new feature”.
Clyde’s Spot was identified as a vigorous plume of gaseous material erupting above the upper cloud layers of Jupiter’s atmosphere.
Foster said that the name “Clyde’s Spot” was coined by fellow planetary imager Paul Maxson from Arizona in the United States, and was quickly adopted by the planetary science community.
While the name remains the unofficial designation of the feature that Foster discovered, having the Juno team refer to it as “Clyde’s Spot” is as official as it gets.
“My sincere thanks to the NASA Juno mission team for the wonderful and positive interaction over this period, in particular Glenn, Candy and Tom, to John Rogers of the BAA, Ricardo and Agustin at the University of Bilbao in Spain, and to my fellow planetary imagers that have committed time and effort to monitoring the development of the outbreak (and continue to do so) since its discovery,” Foster said in a post on Facebook.
“My thanks also to Kevin M. Gill for his processing of the Juno data to produce a totally stunning final image.”
The following image, published by NASA, is the picture that Foster captured of Jupiter with his telescope. NASA overlaid the approximate trajectory of Juno for the Perijoves 27 (PJ27) flyby.
The other images in this article were produced by Kevin M. Gill using data from JunoCam.