ROSETTA’s LAST EARTH SWINGBY

ESA Control Centre, DarmstadtFriday, 13 November 2009

The Rosetta Mission

Dr Gerhard SchwehmRosetta Mission Manager &

Head of Solar System Science Operations Division, ESA

Rosetta - a brief overview

• Rosetta is an ESA scientific cornerstone mission• Initially studied as an ESA/NASA comet-nucleus sample return mission, it later became a European-only mission (with 3 NASA instruments) to perform in-situ measurements at the comet• Rosetta was endorsed by ESA in 1993 and launched in 2004• 67/P Churyumov-Gerasimenko is the final target comet, to be reached in 2014• A very precise injection into interplanetary orbit by Ariane 5 allowed Rosetta to have enough fuel for two asteroid encounters on the way:

- (2867) Steins, 5 September 2008- (21) Lutetia, 10 July 2010

Rosetta firsts

• Rosetta will be the first mission to rendezvous with a comet nucleus and orbit it for an extended period• Rosetta will be the first mission to deploy a Lander (Philae) onto the surface of a comet nucleus.

Rosetta’s objectives

• Bringing a lab to a comet!– determine the physical properties and the

chemical composition of a comet by in-situ investigations

• Study the evolution of the cometary phenomena (coma and tail) while the comet approaches the Sun • Observe at least one asteroid from close by, so to study another class of primitive members of the solar system to understand better how it was formed

Rosetta’s journey to 67P/Churyumov-Gerasimenko

• Basically it is half-time for the mission • A little more than 5 years after launch and a little less than 5 years

to reach the comet• The spacecraft has been performing extremely well and so have the

teams here at ESOC, who are at the controls, at ESAC and the experiment teams

Rosetta’s journey to 67P/Churyumov-Gerasimenko

All major milestones to bring Rosetta to the comet are completed…

Launch 2 March 2004, from Kourou, French Guyana

First Earth swingby, 4 March 2005

Mars swingby, 25 February 2007

Second Earth swingby 13 November 2007

Steins flyby at a distance of 800 km, 5 September 2008

Today final planetary swingby to bring Rosetta on its way to comet 67P/Churyumov-Gerasimenko in 2014.

Rosetta Earth swingby 3Scientific Observations

Dr Rita SchulzRosetta Project Scientist, ESA

• Last planetary swingby of Rosetta• Closest approach: 13 November 07:45 UT, 2,480 km above Earth surface• Moon closest approach: 13 November 15:41 UT at 220,000 km• Remote sensing instruments will perform science and calibration measurements• Limited visibility of Rosetta from Earth (observations from ESA/OGS on Tenerife)• Closest approach over day side• Over night side until shortly before the closest approach over the Pacific Ocean

ROSETTA EARTH SWINGBY 3Scientific Observations

ROSETTA EARTH SWING BY 3Scientific Observations

Participating instruments and science measurements (6-19 November)

RPC All sensors active (9-16 November)Earth-Moon system, plasma & magnetospheric studies

OSIRIS Imaging of Earth (e.g. Berlin, NYC, Atlantic, islands in south pacific) and Moon

ALICE Star occultation by Moon

VIRTIS Earth night-side observations

MIRO Moon studies (search for water)

OSIRIS/VIRTIS/ALICE Auroral search and study, upper atmosphere, oxygen night glow

RosettaCritical swingby events

Andrea AccomazzoRosetta Spacecraft Operations Manager, ESA

Interplanetary Trajectory

Heliocentric speeds:• Earth 30 km/s @ 150 Mkm from the Sun• Comet 33 km/s @ 186 Mkm from the Sun

Rosetta heliocentric speeds:• After launch 30.0 km/s• After 1st Earth swingby 33.8 km/s• After 2nd Earth swingby 35.1 km/s• After 3rd Earth swingby 38.7 km/s

Earth swingby 3

Navigation Towards the Earth

OSIRIS image 12 Nov 2009

Credit: ESA ©2009 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA

The swingby as seen from the Earth

Closest approach (or perigee):- Time 07:45:40 UTC- Altitude 2481 km- Geocentric speed 13.34 km/s or 48,024 km/h

RosettaFuture Mission Milestones

Dr Paolo FerriHead of Solar and Planetary Missions Division

Mission Profile

Future Mission Milestones

• Asteroid Lutetia flyby: 10th July 2010;

• Deep Space Hibernation: July 2011-January 2014;

• Comet arrival: May 2014;

• Landing: November 2014;

• Perihelion: August 2015;

• End of mission: December 2015.