Amateur astronomers have filmed a brief but brilliant flare on Jupiter, thought to be caused by an asteroid or other cosmic missile striking the giant planet’s cloud tops.
A bright spot on May 26, 2017, was first reported by amateur astronomer Sauveur Pedranghelu, who lives in Corsica, France. He was taking a CCD “movie” of Jupiter through his 203mm (8-in) Schmidt-Cassegrain telescope, using a ZWO ASI224MC camera.
The sudden white flash, at 19.24 UT, was captured on 43 frames in the “movie”. It appeared at a latitude of around 51° in Jupiter’s bands and belts. News of the event quickly spread around the internet thanks to another noted observer Damian Peach, fellow enthusiasts Marc Delcroix and Ricardo Hueso Alonso, and astronomy commentator Daniel Fischer in Germany.
Within hours, the possibility that the flare might have been caused by an artefact or flashing satellite was ruled out when two other amateur astronomers found that they had also caught the event in their own images of Jupiter taken at the same time.
German amateur Andre Fleckstein, observing in infrared light, and Thomas Riessler, who is actually a professional astronomer, both recorded a brief flash at the right moment in their own CCD movies of Jupiter.
Reports of their observations, together with enhancements by Marc Delcroix to show the flash more clearly, can be found on the Astrosurf and Astrotreff forums. Marc runs a project to detect impact flashes on Jupiter, and you can find out more about it here.
Four previous flares on Jupiter have been caught by amateur astronomers since 2010, as well as a dark “bruise” in Jupiter’s clouds in 2009 that appeared to be the scar left by an unseen impact.
July 2009: Australian amateur Anthony Wesley was photographing Jupiter with his 14.5-in reflecting telescope at Murrumbateman, near Canberra, when he noticed a dark spot rotating into view in the planet’s south polar region.
Professional astronomers quickly commandeered the NASA/ESA Hubble Space Telescope to take a detailed photo of the impact marking, which resembled those left by fragments of Comet Shoemaker-Levy 9 in 1994.
June 10, 2010: Anthony Wesley captured an impact flash live that was simultaneously photographed by another leading planetary imager, Christopher Go, of Cebu, in the Philippines. It showed as a bright spot on the illuminated region of Jupiter, but close to the terminator that divides day from night.
August 20, 2010: Just two months later, another cosmic impact was recorded on Jupiter by two Japanese astronomers. Masayuki Tachikawa, of Kumamoto city, recorded a photographed his images with a Philips Toucam Pro2 webcam attached to his telescope, a 150mm refractor. It was confirmed by another Japanese observer, Aoki Kazuo, who was also videoing the planet at the time.
September 9, 2012: American amateur astronomer Dan Petersen, of Racine, Wisconsin, observed a flash visually as he was viewing Jupiter with his 12-in Meade LX200 GPS telescope. The impact was confirmed by planetary observer George Hall, of Dallas, Texas, who was videoing Jupiter at the same time through an almost identical telescope.
March 17, 2016: Two amateur astronomers captured video records of a brilliant flash from an impact right on the edge of Jupiter’s visible disk. They were Gerrit Kernbauer, of Mödling, Austria, using a SkyWatcher 20cm (8-in) reflector, and John McKeon, of Dublin, Ireland, observing with an 11-in Schmidt-Cassegrain instrument.
Astronomers woke up to the idea of cosmic impacts on Jupiter being visible from Earth when Comet Shoemaker-Levy 9 disintegrated and sent several chunks colliding with the planet in 1994. The writer remembers witnessing the event thanks to a video camera connected to the 1-metre telescope operated by Dany Cardoen at Puimichel, in the Hautes Provence region of France.
The latest impact shows once again that monitoring Jupiter with CCD cameras can be a useful field to support the work of professional astronomers in finding out how frequently such events occur. Flashes from smaller meteors can also be recorded on the Moon’s night side.