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Bruce Murray Space Image Library

Same place from two very different perspectives

Same place from two very different perspectives
Same place from two very different perspectives In a remarkable coincidence (or maybe not?), at the time Hubble was busy snapping a quadruple moon transit across Saturn's disc - including Titan, Cassini also targeted the hazy moon. Even though they are separated in time by some 76 minutes, at the moment of taking this image it took light exactly 70 minutes to reach Earth from Saturn. Thus the light hitting Hubble's detector above got its start just six minutes after what Cassini saw - practically a simultaneous event (it usually takes several minutes to get 3 color exposures in the first place, anyway). Nevertheless, due to very different vantage points they each saw a completely different scene, practically seeing completely opposite hemispheres of Titan. NASA / JPL-Caltech / Space Telescope Science Institute / SSI / Gordan Ugarkovic

Coincidentally, both views share very roughly the same "up" direction in space. The poster above is a nice juxtaposition of sheer distances involved and resolving power differences. Cassini was at that moment 700 times closer to Titan than Hubble. Both images were enlarged 1.5x from original pixel scale for fairness. Both views use similar filters and were processed identically. In Hubble's case the approx. natural color composite was assembled using the WFPC2 camera F675W, F555W and F439W filters. In Cassini's case, NAC RED, GRN and BL1 filters were used.