IRF logo Project work in Space Plasma Physics
Examensarbete (20 p), spring 2005
The Rosetta Earth flybys

Student: Magnus Billvik
Supervisor: Anders Eriksson

Swedish Institute of Space Physics, Uppsala
Department of Astronomy and Space Physics, Uppsala University


Rosetta is an ESA (European Space Agency) spacecraft, launched towards a comet in March 2, 2004. To be able to catch up with the comet, Rosetta has to take a long route through the planetary system, including three flybys of Earth and one of March. At the Swedish Institute of Space Physics in Uppsala, we have built an instrument called LAP (Langmuir probe) to study the ionized gas (plasma) close to the comet. However, this instrument and its companion instruments in the Rosetta Plasma Consortium, RPC, can be used also for exploring space around Mars and Earth during the flybys. The Mars flyby is highly interesting, as very few spacecraft with reasonable plasma instrumentation have ever visited Mars. As an example, none of the spacecraft now at Mars have anything to match the RPC instrumentation.

While the Mars flyby is of obvious scientific interest, the Earth flybys may at first sight seem to be less fun. Around Earth, there are of course a lot of measurements made by instruments on spacecraft specifically constructed to observe the near-Earth space environment. However, there are several reasons for doing plasma science with RPC during the flybys: (1) calibration of instruments in a reasonably known environment; (2) rehearsal for the Mars flyby -- do the operational modes we want to use really give the desired results, or should we change them slightly?; and (3) a real scientific interest also at Earth: during the flybys, Rosetta will be an extra measurment point around Earth, and multispacecraft studies are vital for understanding geospace.

In order to get the most out of the Earth and Mars flybys, careful planning is needed, including modelling of the environment. This is the topic of the present work.


Magnus developed Matlab routines for reading, manipulating and visualizing orbit and attitude information, and used it to prepare for the first Rosetta Earth flyby (March 4, 2005). He modelled the expected radiation dose, thereby building the basis for our decision to stay on during the flyby. He compared some results to data gathered during the flyby, and provided overview of the remaining Earth and Mars flybys. The project was completed in June 2005.


Anders Eriksson,

  [Rosetta interplanetary trajectory 2004-2014]
Rosetta interplanetary trajectory.
(1) Launch, 2 March 2004.
(2) First Earth swingby, 3 March 2005.
(3) Mars swingby, 26 February 2007
(4) Second Earth swingby, 14 November 2007
(5) Asteroid flyby
(6) Third Earth flyby, 11 November 2009
(7) Asteroid flyby
(8) Arriving at the comet in 2014
last modified onMonday, 29-Aug-2005 14:25:59 CEST