A quick final update on spacecraft activity for the next few days, provided by Mars Express Spacecraft Operations Engineer Hannes Griebel here at ESOC:
  • The final pre-flyby orbit determination was concluded earlier this week; this precise calculation of the Mars Express orbit was used to generate the commands for the flyby
  • These commands include all necessary pointing and instrument instructions so that the flyby and science observations can be conducted automatically
  • They were uploaded to the spacecraft this morning during a ground station pass at 07:00 UT (08:00 CET)
  • Mars Express is now in an orbit with respect to Mars ranging from approximately 400 km to 10 000 km; it will pass by the centre of Phobos on Sunday at just 111 km
  • On Sunday, 9 January, Mars Express will automatically slew to point instruments toward the expected direction of Phobos starting at 13:55 UT (14:55 CET) - it will stay in this pointing mode for 5 minutes and 46 seconds
  • Closest approach occurs at 14:06:30.016 UT (15:06:30.016 CET)
  • A few minutes later, after closest approach, it will slew back to Earth pointing and the next ground station pass, via ESA's 35m DSA-2 deep space station at Cebreros, Spain, will begin at 14:57 UT (15:57 CET). Data will be downloaded progressively over the following days(see "When can we expect first images" below)
At this time, the one-way signal travel time is 19 mins:47.4 seconds and Mars Express is 355 959 424 km from Earth.

Mars Express Spacecraft Operations Manager Michel Denis added:
"The simple fact that this flyby is being done automatically and with little human activity on the days around and during closest approach hides the large amount of work done by the operations team, the flight dynamics team, the mission scientists and the principle investigators to get ready. We are looking forward to a smooth flyby and some very interesting results."

Overall, it's a quiet but nonetheless exciting phase of the mission that promises to provide some excellent and valuable Phobos images and data from close up! We'll update you on Monday as soon as we hear any word from the team at ESOC.  -- Daniel