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Fri, 09 Jun 2017

Jupiter as you've never seen it before

 Alan Clitherow writes:

When Nasa’s Juno probe completed its closest approach to the cloud tops of Jupiter on its sixth extended orbit around the giant planet, it took a series of high-resolution images that surpass the best images seen from any other probe so far. These have been stitched together into an animation by Gerald Eichstadt and Sean Doran which has been placed on YouTube and can be viewed here:

Be prepared: this video is a kaleidoscopic experience, helped by the choice of background music, being a choral extract from the ‘traversing the stargate’ scenes in the movie 2001 – A Space Odyssey. The level of detail on view is quite amazing and should be viewed in the highest definition available. Juno passed from north to south starting at altitude above the North Polar Region, then diving lower and lower to skim the Equatorial Zone then slowly rising again, above the South Pole.  Simply not to be missed.

Another impact on Jupiter

Given that Jupiter is the second largest object in our Solar System, after the Sun itself, and that the planet has a powerful gravitational field of its own, it would be surprising if it were not occasionally pelted with debris from space in the same way that the Earth has regular meteor showers and the occasional larger fireball from the impact of relatively small rocky and icy bodies. Given the large and variable distance that Jupiter is from Earth it is less surprising that impacts in its own atmosphere are only rarely observed. In fact, the first time such impacts were definitely confirmed followed the breakup of comet Shoemaker–Levy 9 when a large number of fragments from the comet rained down on Jupiter causing massive explosions in its atmosphere and scarring the cloud-tops with dark marks at the sites of these explosions; this took place in 1994.

Since then the equipment used by amateurs to observe the planets have increased in sensitivity and relatively modest ‘back-yard’ telescopes equipped with modern cameras are quite capable of detecting the flash of infrared light made by objects burning up in the atmosphere of Jupiter. In fact there have now been 5 such impacts recorded by amateurs since the Shoemaker-Levy 9 events; one in 2009, two and three in 2010, number four in 2016 and now the fifth event recorded on the 26th of May this year.

European amateur Saveur Pedranghelu recorded the impact flash from Corsica, over 43 frames of video shot just after 19.24 UT, using a 203 mm aperture SCT fitted with an ASI224 one-shot-colour video camera. His result was confirmed by a report made shortly afterwards from Thomas Riessler in Germany shot at precisely the same time. The flash was visible for approximately eight-tenths of a second and both reports were collated and confirmed by Marc Delcroix, an expert amateur based in France who runs a website specifically to detect and confirm genuine impacts.

So far no SPA member has reported seeing any such bright flash within videos shot on that day; however, there may be more such events hidden in amateur data. It is important to review any videos of Jupiter looking for impact events, not just to process and stack the video to produce a single sharp image; a transient event of this duration would probably not be detected by the stacking software used by most amateur planetary photographers and would not appear in the final image, whereas the flash would be quite obvious to the human eye if watching a video stream.

It is certain that more such events will be captured by the amateur community and this will give the scientific world a better idea of the frequency of impacts at Jupiter, and by association the likelihood of major impacts on Earth!

Jupiter is currently in the evening sky over in the south-west, and at the moment is the brightest object in the evening sky after the Moon. 


Added by: Robin Scagell