Image NASA/JPL/University of Arizona
As the most powerful telescope outside Earth orbit, HiRISE spends most of its working hours in orbit around Mars surveying the surface and sending back stunning high-res images. You can browse some of them at the HiRISE website. But sometimes scientists point the camera up instead of down -- as was the case with this stunning photo of Jupiter, as seen from Mars orbit, which they took in order to test the camera's controls .
This image of Jupiter and its major satellites (10 MB) was acquired to calibrate the pointing and color response of the camera. An oversight in planning this unusual observation put the focus mechanism in the wrong location, blurring the image. This does not detract from the calibration objectives, but makes the raw image less esthetic.Pretty cool photo -- especially for a grab shot with a camera that was not quite set right and that had to be "sharpened" electronically at home. Sounds familiar.
To compensate, the image has been "sharpened" on the ground by Dennis Gallagher, the HiRISE chief optical designer. With this sharpening, and because Mars is closer to Jupiter than Earth is, this image has comparable resolution as the Hubble Space Telescope's pictures of Jupiter.
The colors are not what is seen by the human eye because HiRISE is able to detect light with a slightly longer wavelength than we can (that is, the infrared).