Velocity field of Jupiter's Great Red Spot in December 2016
Data files
Feb 03, 2020 version files 31.43 MB
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outGridVelocity.h5
31.43 MB
Abstract
Hubble Space Telescope (HST) data acquired around 2016-12-11 16:00 UT were used to measure the velocity field of Jupiter's Great Red Spot. The Hubble dataset is described in Tollefson et al. (2017) and Wong (2017), and the velocity extraction was performed with the ACCIV method described in Asay-Davis et al. (2009). A small subset of the resulting gridded velocity field is shown in a paper discussing small-scale waves observed with Juno's JunoCam imager (Orton et al. 2020), to compare the local wind field from the HST data with small-scale waves observed in JunoCam image 114. The velocity field that is shown in Fig. 6 of Orton et al. (2020) is an excerpt from the larger velocity field presented here.
- Short timesteps (45 min.) had to be used to be used for Fig. 6 of Orton et al. (2020), because strong turbulence in this region means that cloud tracers may not be coherent over a full Jupiter rotation (about 10 hrs).
- For studies of the Great Red Spot itself, this velocity field is not ideal because it does not use long-time separated data (i.e., 10-hr separations; see Asay-Davis et al. 2009).
- The mean (over the full velocity field) 1-sigma correlation uncertainty error is 17 m/s.
Data file is in the HDF5 format. It contains the following elements:
bounds Dataset {4} dataX Dataset {701, 1401} dataY Dataset {701, 1401} vx Dataset {701, 1401} vy Dataset {701, 1401}
bounds - values are max west longitude (System III), min west longitude, min latitude (planetographic), max latitude. These bounds are used to define the regularly-gridded coordinates of the velocity data. Positions step in (e.g. for longitude) 1401 evenly-divided steps from 30 deg W to -40 deg W, inclusive (so, 0.05-deg steps).
dataX - not used (relic of older format)
dataY - not used (relic of older format)
vx - velocity in units of m/s. Positive values are eastward.
vy - velocity in units of m/s. Positive values are northward.