End of Rosetta mission signals new beginning


Researchers will begin a more active research phase. Rosetta measurements have been carried out at Aalto University from August 2014.


The image shows the orbits of the comet and the planets. Along the comet's orbit, there are simulations of the comet's interaction with solar wind at different distances from the Sun (3.3; 2.4 and 1.3 AU). AU is an astronomical unit, i.e. the distance from the Earth to the Sun ~145 million km. Photo: Markku Alho / Aalto University

The end of Rosetta mission signals the beginning of a new phase for Aalto University researchers. The European Space Agency's mission control centre located in Germany has sent the Rosetta probe a command to crash into the 67P/Churyumov-Gerasimenko comet. Impact is due to take place today 30 September at 2 pm Finnish time. The flight leading up to impact has lasted 12.5 years and is one of the most successful throughout the history of space research

'We at Aalto University have worked in collaboration with other institutes in the collection of data on the comet’s entire life-cycle: the birth of the comet, its growth, its active adulthood and its decline to slumber, from which it will awaken in four years' time, when the new comet reaches the heat of the Sun again,' Professor Esa Kallio details.


The image shows in order from left to right the development of the comet's particle environment from the perihelion to the end of measurements. The cloud depicts the water ions in the comet's environment, the lines the movement of the solar winds. From the left: 1.3 AU is an ”adult” comet, 2.4 AU a ”teenager” and 3.3 AU is just about to be born. The effect the comet has on solar wind varies a great deal depending on the comet's level of activity. Photo: Markku Alho / Aalto University

Although the Rosetta mission is coming to an end, the active research phase is only just beginning.

'Researchers now have time to focus on the analysis of measurements, whereas up until now they have had little time for anything but fine-tuning the characteristics of the measurement devices. We are modelling the comet, and we now have all the possible measurement materials at our disposal to improve the model and carry out comparisons with measurements,' Professor Kallio explains.

Aalto University has carried out Academy of Finland-funded research work for the entire span of Rosetta measurements starting in August 2014.

'One of the most interesting scientific results has been discovering how water found on the comet differed in its characteristics from that found on Earth. Our team was also surprised that the comet became active and created "a water source" at such an early stage far from the Sun,' Professor Kallio states.

Also read:

News item 23 January 2015: The Rosetta probe witnessed the awakening of the icy comet

News item 12 August 2015: The journey of the comet tracked by the Rosetta probe will come to its climax on 13th August

See the animation video

Further information:
Professor Esa Kallio
Aalto University
tel. +358 50 4205 857

Doctoral candidate Markku Alho
Aalto University
tel. +358 50 3837 805