LOOK: 'Great Cold Spot' Found on Jupiter's Upper Atmosphere
Astronomers from the University of Leicester have discovered a second great spot in the upper atmosphere of the gas giant, Jupiter.
The second great spot, described in a paper published in the journal Geophysical Research Letters, is about 7,500 miles wide and 15,000 miles across. Dubbed as the "Great Cold Spot," researchers believe that the second great spot was created from powerful energies exerted by Jupiter's polar aurorae.
"The detection of the Great Cold Spot was a real surprise to us, but there are indications that other features might also exist in Jupiter's upper atmosphere," said Dr. Tom Stallard, Associate Professor in Planetary Astronomy and lead author of the study, in a press release. "Our next step will be to look for other features in the upper atmosphere, as well as investigating the Great Cold Spot itself in more detail."
Using the CRIRES instrument on the Very Large Telescope (VLT), the researchers observed spectral emissions of H3+, an ion of hydrogen present in large amounts in Jupiter's atmosphere. By doing so, the researchers were able to map the mean temperature and density of Jupiter's atmosphere.
Images of the H3 emissions in the planet's ionosphere that were capture using NASA's InfraRed Telescope Facility between 1995 and 2000 were then compared with the spectral emissions of H3+ observed by the VLT.
The researchers found that there is an area of darkness among the hot environment of the planet's upper atmosphere. Just like the Great Red Spot, the researchers observed that the Great Cold Spot stayed at the same place across 15 years. However, the Great Cold Spot is more volatile than the Great Red Spot. The cold spot experience a dramatic change in size and shape over a few days or weeks.
The Great Cold Spot is thought to be formed by Jupiter's polar aurorae, which drives energy into the atmosphere in the form of heat flowing around the planet. This process could create a region of cooling in the atmosphere, which could then drive the development of a vortex similar to the Great Red Spot.