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Rosetta Project

Rosetta Orbiter, ESA

ESA's Comet Chaser Rosetta (link to ESA Rosetta Homepage)

Where exactly is Rosetta now? Click here for an on-line update

News: Rosetta status update April 16, 2014: COSAC was activated successfully recording background gas spectra. SESAME continues to operate successfully. Only the interference test with the radio system is still missing, scheduled for next week. With the successful test of the EEPROM part of the Lander's Mass Memory, provided by FMI, the commissioning of this system element is successfully concluded.

April 15, 2014: Philae's camera Civa generated successfully its first images, the landing gear motor and the deployment motor of the APXS instrument were successfully moved. SESAME with FMI's PI-instrument PP performed successfully its first complete measurements after hibernation. All results are nominal without deviation from the status before hibernation.

Next days' activities: interference tests between instruments and the radio system, detailed memory tests of Philae's central computer.

April 10, 2014: The Rosetta orbiter system and instruments are now commissioned. No significant problems were found so far. Especially all Finnish contributions to the orbiter instruments were working well by the end of the commissioning phase on April 4.

During April 9 the first tests with the FMI-provided Lander mass memory were completed successfully. Further tests continue during the following 7 days. Also the integrity of the software included in the SESAME instrument with its FMI-contribution PP was successfully verified. All measured temperatures and currents were in the expected range. The correct operation of the Lander instruments and the Landing Gear mechanics will be tested during the following days until April 24.

Earlier reports:

On March 28 the Lander Philae was successfully switched on for the first time after hibernation. The updated control software was uploaded and successfully verified. All Lander system components tested so far are working nominally. The most important change in the software is the way how the harpoons will be fired after touch down, as during the past years a problem was detected with the reference model on ground. According to the new strategy both harpoons will be fired at the same time opposed to the initially planned sequential activation. The harpoons will anchor the Lander securely to the comet when drilling a hole for sample retrieval. Without anchoring the lander would be lifted in the low gravity environment rather than the drill entering the ground.

On March 27 the cameras on board Rosetta have caught a first glimpse of its destination comet since end of its hibernation phase in January.

The power levels and temperatures for orbiter and Lander are as expected and indicate that no deterioration of system components has happened during the 31 months hibernation phase. Also the solar panels do not show degradation in their performance. All reaction wheels needed for steering the spacecraft are operating nominally - good news as there were some indications before hibernation that one of the 4 units might develop a problem. The slight delay of the first contact on Monday was caused by an automatic rebooting of the on-board computer right after exiting the hibernation phase earlier during the day, delaying all subsequent activities somewhat. The reason is currently under investigation, but there is no impact on the further mission.

On January 2014 at 10:00 UTC Rosetta was programmed to exit the hibernation phase. After warming up of the star trackers and after the completion of a system self check the thrusters were fired at around 16:00 UTC to stop the satellite spinning. Using the sky images recorded with the system cameras and comparing them with stored star locations the spacecraft changed its orientation automatically such that it was getting maximum solar energy input via its solar arrays.  Then the large dish antenna was pointed towards Earth. With a signal travel time of about 45 minutes for the 673 million kilometer distance the first signal was received on Earth 18:17 UTC or 20:17 Finnish local time. ESA's control center ESOC in Darmstadt / Germany sent the first confirmation commands to the spacecraft terminating the autonomous contact phase. Since then several data packages have been exchanged between ESOC and the satellite. Detailed technical information received via telemetry during the night and the early morning hours of January 21 indicate that the most important system parameters of orbiter and Lander are nominal and as expected.

Animations of the wake-up process generated by the ESA team can be found via the ESA Rosetta home page or directly here as 60 MByte AVI film.

The complete orbit history is displayed in this 9 MB AVI-animation.

Rosetta and Finland:

Rosetta was Finland's first major space science project after it joined ESA as full member in 1995. With the orbiter structure built by Patria, Tampere, and FMI's participation in 6 different instruments on board the orbiter and Lander, this was a major effort involving several Finnish companies. Strengthening the international cooperation to the major European players in the space sector this placed Finland firmly onto the European map as a thought-after partner in joined space technology ventures. In the subsequent years several Finns held high-ranking positions of trust in the European space community.

Rosetta entered hibernation:

On June 8 2011 at 07:30 UTC Rosetta was spun-up to stabilise its attitude in view of the hibernation mode.The spacecraft behaviour, as far as we could monitor, was excellent and allowed the flight control team at ESOC in Darmstadt to release the command to enter hibernation mode later in the afternoon. The last RF pulse from the spacecraft was detected at ca. 14:12:00 UTC as expected and after that no further signal could be seen from the spacecraft thus confirming a successful hibernation entry.

Presentation of Rosetta Payload (FMI) large (47MB PDF)smaller (21,5MB PDF)


FMI's contributions to the Rosetta Lander Philae:

The Permitivity Probe PP as part of Philae's instrument group SESAME; Principle Investigator: Walter Schmidt, FMI

The autonomous Mass Memory of Philae's Central Data Management System CDMS


FMI's contributions to the Rosetta orbiter:

The dust spectrometer COSIMA

The Langmuir Probe LAP as part of the Rosetta Plasma Consortium (RPC)

The Ion Composition Analyzer ICA as part of the Rosetta Plasma Consortium (RPC)

The Multi Impedance Probe MIP as part of the Rosetta Plasma Consortium. FMI provided the Electrical Ground Support Equipment (EGSE) for instrument development support.

 FMI supports the Rosetta project via extensive data analysis and modelling efforts, mainly concentrating on the plasma- and dust environment of the comet. This activity is funded by a grant from the Finnish Academy of Sciences