content 23-October-2017 10:07:35

Fact Sheet

 Fast Facts


Launch date: 2 March 2004 07:17 UT
Mission end: end September 2016 (extended mission)
Launch vehicle: Ariane 5 G+ from Kourou, French Guiana
Launch mass: 3000 kg (fully fuelled); Orbiter: 2900 kg (including 1670 kg propellant and 165 kg science payload); Lander: 100 kg
Mission phase: At Comet 67P/Churyumov-Gerasimenko
Orbit: En route to Comet 67P/Churyumov-Gerasimenko, Rosetta completed a complex trajectory that included four gravity assist manoeuvres (3 × Earth, 1 × Mars). The spacecraft arrived at the comet on 6 August 2014. Since then, the spacecraft has been orbiting the comet. It will accompany the comet on its journey around the Sun.
Objectives: To study the origin of comets, the relationship between cometary and interstellar material, and its implications with regard to the origin of the Solar System. The measurements to be made to achieve this are:
  • Global characterisation of the nucleus, determination of dynamic properties, surface morphology and composition;
  • Determination of the chemical, mineralogical and isotopic compositions of volatiles and refractories in a cometary nucleus;
  • Determination of the physical properties and interrelation of volatiles and refractories in a cometary nucleus;
  • Study of the development of cometary activity and the processes in the surface layer of the nucleus and the inner coma (dust/gas interaction);
  • Global characterisation of asteroids, including determination of dynamic properties, surface morphology and composition.

The International Rosetta Mission was approved in November 1993 by ESA's Science Programme Committee as the Planetary Cornerstone Mission in ESA's long-term space science programme. The mission was originally set for a rendezvous with Comet 46 P/Wirtanen. After postponement of the original launch a new target was set: Comet 67P/Churyumov-Gerasimenko. During its 10 year journey towards the comet, the spacecraft has passed by two asteroids: 2867 Steins (in 2008) and 21 Lutetia (in 2010). Rosetta arrived at the comet on 6 August 2014 and following deployment of the lander, Philae, on 12 November, the orbiter is accompanying the comet through perihelion and back to deep space until the mission ends in September 2016.

Mission Objectives

Artist's impression of Rosetta and Philae at the comet. Credit: ESA/ATG medialab; Comet image: ESA/Rosetta/NavCam

Rosetta's main objective is to rendezvous with, and enter orbit around, comet 67P/Churyumov-Gerasimenko and to perform observations of the comet's nucleus and coma. During the period that Rosetta orbits the comet, 67P/Churyumov-Gerasimenko will reach perihelion (the closest point to the Sun in its orbit), allowing for the resulting increase in activity to be measured. On 12 November, a lander named Philae was deployed and made the first soft landing on a comet.


Mission Name

Rosetta takes its name from the Rosetta Stone, an incomplete stela of black basalt incised with the same priestly decree concerning Ptolemy V,  in three scripts. Although three scripts are shown (Egyptian Hieroglyphs, Egyptian Demotic and Greek) just two languages are represented. The great significance of the Stone is that it provided the key to deciphering Egyptian hieroglyphs. Scientists hope that the Rosetta mission will unlock the mysteries of how the Solar System evolved. 

Rosetta's lander Philae is named after an island in the Nile river, where archaeologists found an inscription on an obelisk that confirmed their interpretation of the Rosetta Stone texts.



The Rosetta design is based on a box-type central structure, 2.8 m × 2.1 m × 2.0 m, on which all subsystems and payload equipment are mounted. Two solar panels, with a combined area of 64 m², each stretch out to 14 m in length.  The total span from tip to tip is 32 m.  The Philae lander, measuring about 1 m × 1 m × 1 m (before deployment of its landing gear), is attached to the spacecraft side opposite to the side that carries the 2.2m diameter steerable high-gain antenna.


The Rosetta orbiter (left) carries an instrument suite of 11 science instrument packages along with the Philae lander (right) which carries 10 science instrument packages. Credit: ESA/ATG medialab.


The Rosetta Orbiter (11 science instrument packages)

Alice Ultraviolet Imaging Spectrometer
CONSERT Comet Nucleus Sounding Experiment by Radio wave Transmission
COSIMA Cometary Secondary Ion Mass Analyser
GIADA Grain Impact Analyser and Dust Accumulator
MIDAS Micro-Imaging Dust Analysis System
MIRO Microwave Instrument for the Rosetta Orbiter
OSIRIS Optical, Spectroscopic, and Infrared Remote Imaging System
ROSINA Rosetta Orbiter Spectrometer for Ion and Neutral Analysis
RPC Rosetta Plasma Consortium
RSI Radio Science Investigation
VIRTIS Visible and Infrared Thermal Imaging Spectrometer

The Rosetta Lander (10 science instrument packages)

APXS Alpha Proton X-ray Spectrometer
ÇIVA and ROLIS Panoramic and microscopic imaging system
CONSERT Comet Nucleus Sounding Experiment by Radio wave Transmission
COSAC Cometary Sampling and Composition experiment
PTOLEMY Evolved Gas Analyser
MUPUS Multi-Purpose Sensor for Surface and Subsurface Science
ROMAP Rosetta lander Magnetometer and Plasma Monitor
SD2 Sample and Distribution Device
SESAME Surface Electric Sounding and Acoustic Monitoring Experiment


Journey milestones

Event Nominal date
Launch 2 March 2004
First Earth gravity assist 4 March 2005
Mars gravity assist 25 February 2007
Second Earth gravity assist 13 November 2007
Asteroid Steins flyby 5 September 2008
Third Earth gravity assist 13 November 2009
Asteroid Lutetia flyby 10 July 2010
Enter deep space hibernation 8 June 2011
Exit deep space hibernation 20 January 2014
Comet rendezvous manoeuvres begin 7 May 2014
Arrive at comet 6 August 2014
Start global mapping of comet 10 September 2014
Lander delivery 12 November 2014
Perihelion passage 13 August 2015
Mission End September 2016


This animation tracks Rosetta's journey through the Solar System, using gravity slingshots from Earth and Mars to reach its final destination: comet 67P/Churyumov-Gerasimenko. Copyright: ESA. Click here for video details.


Last Update: 22 March 2017

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