Projections of two rotations from a Cycle for Jupiter, Uranus, Neptune, and Saturn. Watch how cloud features change between rotations.
OPAL is a project to obtain long time baseline observations of the outer planets in order to understand their atmospheric dynamics and evolution as gas giants. The yearly observations from OPAL throughout the remainder of Hubble's operation will provide a legacy of time-domain images for use by planetary scientists. The project will ultimately observe all of the giant planets in the solar system (Jupiter, Saturn, Uranus, and Neptune) in a wide range of filters. The images are processed using an ellipsoid limb-fitting technique, with an additional fringe correction applied to the narrow-band filters only (e.g., FQ889N for Jupiter 2014-2015), which amounts to a few percent correction. Mosaics are created for each observed filter in a projection that spans 360 degrees of longitude. See the README files (on disk or in the tables below) for additional details on the data processing. The mosaics from each filter (in FITS format), as well as previews (in TIF format) are provided.
Each file name begins with the same prefix: "hlsp_opal_hst_wfc3-uvis_". The name of the planet is the next part of the filename. Each rotation/epoch is differentiated by a calendar year and a letter, e.g., "jupiter-2015a" is the first rotation of Jupiter from Cycle 22, "jupiter-2015b" is the second rotation from Cycle 22, etc. Keep in mind that HST cycles span two calendar years, since they start in Oct. and run through Sep. of the following year. The next part of the filename includes the HST filter for that mosaic/preview image, followed by a version number and the file extension. File extensions are:
_globalmap.fits = Mosaic (projection) for the given filter.
_globalmap-medium.tif = Preview image (width x height ~ 900 x 450 px, varies by target).
_globalmap-small.tif = Preview image (width x height ~ 450 x 225 px, varies by target).
_globalmap.tif = Preview image (size varies by target).