[BAA-ebulletin 00801] Jupiter’s Great Red Spot: a pro-am collaborative project

[BAA electronic bulletins service]

Jupiter’s Great Red Spot: a pro-am collaborative project


Observers have noticed that one feature of Jupiter this apparition has 
been the small size, and strong reddish colour, of the Great Red Spot.  
Not only has its long-term shrinkage proceeded so it is smaller than 
ever before; we have also found that its internal rotation has speeded 
up.  We measured the internal circulation of the GRS on images taken by 
many amateur observers in 2014 Jan. and found a rotation period of only 
3.6 days, shorter than any previous ground-based measurement, and 
evidence that the wind speed may also have increased. All this has 
happened just as an intense outbreak of spots on the adjacent eastward 
jetstream has been interacting with the GRS, suggesting a possible 
physical link. Our report was posted at:

http://www.britastro.org/jupiter/2013_14reports.htm
[Report no.7], and:

http://alpo-j.asahikawa-med.ac.jp/kk14/j140406s.htm

and has been covered in news items at:

http://www.skyandtelescope.com/astronomy-news/observing-news/jupiters-great-red-spot/

http://www.universetoday.com/108257/will-jupiters-great-red-spot-turn-into-a-wee-red-dot/

Acting on this evidence, Dr Amy Simon and colleagues got time at short 
notice for the Hubble Space Telescope to image the GRS on April 21.  A 
press release with the first colour image is at:

http://hubblesite.org/newscenter/archive/releases/solar-system/2014/24/

The Hubble images, taken ~10 hours apart, are now being used to 
investigate the GRS rotation and its interaction with the jetstream 
spots, in the hope of finding out why the GRS is shrinking and what 
drives its winds.  Through this project, we hope that amateur 
observations may lead to a significant advance in understanding 
Jupiter’s atmospheric dynamics.

John Rogers
BAA Jupiter Section Director