HWGA<br /><br /><br />When the Cassini craft emits a radio pulse from it's large dish at an astronomical object, and records the echo of the signal that bounces off the object, (conventional definition of RADAR) the useful range of this technique is severly limited in range by the double inverse square effect.<br /><br />Cassini can only, for instance, radar map Titan when it is only a few thousand kilometers away.<br /><br />Cassini never approached Jupiter anywhere remotely close enough for this technique to be used.<br /><br />Approaching Saturn close enough would be a very extreme manuver for a very valuble resource.<br /><br /><br />The radar instrument can also be employed in a passive mode, utilizing the natural RF emissions of various objects for study.<br /><br />Since these observations are based on essentially wide band random RF 'noise', mapping cannot be done. But, information about surface roughness, temperature and maybe composition can be studied this way.<br /><br />Such observations of many objects can and will be done.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>