MTP015:                                                                       
                                                                              
one navigation image was not acquired or lost at downlink:                    
                                                                              
          <block ref='MWNV'>                                                  
            <startTime>2015-04-16T16:19:17</startTime>                        
            <endTime>2015-04-16T17:19:17</endTime>                            
            <metadata>                                                        
              <mntBlockNumber>2790</mntBlockNumber>                           
            </metadata>                                                       
          </block>                                                            
                                                                              
one context image at 2015-04-25T13:20:00 was skipped because it conflicted    
with a Star Track CCD read-out