What is happening on Jupiter?

[Ed in Houston]

The great red spot on Jupiter has been shrinking since it's discovery in the 17th century after the invention of the telescope. In 1881 Thomas Gwyn Elger made the following drawing of Jupiter showing it's elongated appearance. The GRS is a long lived storm rotating like a giant Hurricane. The rate of rotation of the GRS has been increasing as it h shrinks in size much like an ice skater spinning faster as the skater's arms are pulled inward. It is the conservation of angular momentum.

 

 

Animation of Jupiter as the Voyager spacecraft approached.

 

 

 

Jupiter reached opposition for the 2015-2016 apparition on March 8th 2016. High resolution amateur images provide the detail to calculate the GRS' period and size. GRS rotation can be detected in images as little as one hour apart. Images from the 2014/2015 apparition showed the rotation period to be about 3.7 days while the GRS continues to shrink in size as the rotation rate slowly increases.

 

 

Close up image (left) of the GRS by Christopher Go showing much internal detail. On the right are images by the HST showing how the GRS has been shrinking from 1995 to 2014.

 

On March 17th 2016, an asteroid impact event on Jupiter was captured on video independently by John Mckeon and Gerrit Kernbauer. The videos were processed into still images by Marc Delcroix and are presented at the following two URLs. The asteroid can be seen near Jupiter's limb at the moment of impact.

 

http://www.astrosurf.com/delcroix/images/j20160317-00h18.7UT-JMK.png

 

http://www.astrosurf.com/delcroix/images/j20160317-00h18.6UT-GKe.png

 

Although the impact was easily detected, the momentum energy transferred to Jupiter was insufficient to leave an impact scar in Jupiter's atmosphere. The impact site was determined to be at L2 = 281.1 longitude and +12.4 degrees latitude. About 17 hours after the impact, R. Iwamasa captured Jupiter at CM2 of about 262 that shows no disruption of the atmosphere.

 

http://zetta.jpn.ph/alpo/kk16/j160317n5.jpg

 

Ed in Houston