The instrument observed a wavelength range between 3. The majority of Jupiter's aurorae are produced as a result of continuously driven internal current systems, driven by plasma from Io, with regions of auroral heating fixed at the same jovigraphic latitudes and longitudes. This gentle gradation in emission is suggestive of a diffuse thermal gradient away from Jupiter's dynamic aurora. Thermosphere model simulations and some supporting observations indicate the presence of vortices with cold centers and that these vortices and associated temperatures will vary with geomagnetic activity [e. As explained in Walterscheid and Crowley [ ], a cyclonic thermosphere vortex will produce a cold center when Coriolis is stronger than centrifugal forces, meaning relatively low wind speeds and modest radius of curvature in the wind vortex. 
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Introduction The upper atmosphere of a jjupiter represents an important boundary region between the underlying atmosphere and the surrounding space environment, consisting of the coexisting neutral thermosphere and charged ionosphere.
Between andthere are significant variations in this region, but no clear spot, and from onward a clear dark region occurs within each of these images, evolving in location and morphology. These observations were made on a 17 October and b 31 December The thermosphere is dominated by inputs from the atmosphere below, heating from the Sun, and, for magnetized planets, indirectly through currents that form between the ionosphere and the surrounding magnetosphere.
Past observations of Jupiter's stratosphere reveal a localized hot spot focused on the auroral region near system III longitude [ Livengood et al. Thermosphere model simulations and some supporting observations indicate the presence of vortices with cold centers and that these vortices and associated temperatures will vary with geomagnetic activity [e.
The morphology of the dark region also sometimes appears considerably distorted, but it typically forms a roughly oval shape.
Hsu7 and Rosie E. Ethane as a probe of the millibar regionJ.
The Great Cold Spot in Jupiter's upper atmosphere
A brief reviewProg. The imbalance of flows for a vortex can result in a cold center depending on the direction of rotation and the relative magnitudes of Coriolis, centrifugal, and pressure gradients.
The detection of a localized region of cooling within the upper atmosphere is unexpected. A, —, doi: One possible driver for localized dynamics could be an underlying weather system propagating localized winds from the lower stratosphere or troposphere. Support Center Support Center.
Jupitar - Badman Place (Prod By Genius Selection)
Past observations and modeling of Jupiter's thermosphere have, due to their limited resolution, suggested that heat generated by the aurora near the badmab results in a smooth thermal gradient away from these aurorae, indicating a quiescent and diffuse flow of energy within the subauroral thermosphere. This is also a spectral region in which there is significant hydrocarbon absorption by the underlying, immediately lower atmosphere, which effectively removes any reflected sunlight from the spectra.
These data were flat fielded, straightened using sky lines, and flux calibrated using light from an A0V star, in the usual manner. The combination of these forces can lead to sustained vortex structures in the thermosphere that induce secondary circulations resulting in adiabatic cooling of the vortex core creating cold spots [ Walterscheid and Crowley]. Details of the instrument settings and techniques used are also described in baman supporting information.
Given that the GCS is observed over an extended period of time, any magnetospheric source would have to be fixed in system III longitude and long lived, or the affect of the source would be averaged out across all system III longitudes.
Cassini VIMS observations of H3+ emission on the nightside of Jupiter
In contrast with this, the column densities in both the dark region and the surrounding ionosphere appear to be similar, though the errors associated with the calculated column densities are too large to be certain that there is not also a significant change in density within this region. It is also notable that when scaled in this way, the weakest emission no longer follows the outline of the main auroral oval but instead appears to broadly follow lines of jovigraphic latitude.
As explained in Walterscheid and Crowley [ ], a cyclonic thermosphere vortex will produce a cold center when Coriolis is stronger than centrifugal forces, meaning relatively low wind speeds and modest radius of curvature in the wind vortex.
In order to better understand the dynamics of the feature, we need to identify and characterize the GCS over a much longer time frame. As we have seen, models predict that auroral energy deposited into the thermosphere is likely to migrate around the planet along lines of equal jovigraphic longitude.
We do not know how long this is, but given the slow pace of change within the Earth's magnetic field, the Great Cold Spot has existed for thousands of years, and perhaps much longer.
Energy inputs and thermal balanceIcarus2—, doi: This feature occurs on both 17 October and 31 December and appears to corotate with the planet on 31 December. During the period between andJ.
Since this feature is unlikely to be driven by the atmosphere below the ionosphere, or by direct interactions with the magnetosphere, this suggests that the GCS originated from processes that occur within, or at close altitudes to, the thermosphere. The measurement of ion windsIcarus, —, doi: In early years, between andalthough there is localized variability, no clear spot can be seen. A generalized inverse jupited of imagesBwdman, 1—23, doi: Within Jupiter's lower atmosphere, boundary regions between two regions of bulk flow with different energies often form relatively small and stable vortexes [ Ingersoll].
This data set was recently reprocessed by Badmqn. Global structure and dynamics driven by auroral and Joule heatingJ.
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