Rosetta factsheet

Name: Rosetta

Mission: To rendezvous with Comet 67P/Churyumov-Gerasimenko and study the nucleus of the comet and its environment for nearly two years, and land a probe on its surface.

Primary mission objectives:

• Undertake a lengthy exploration of a comet at close quarters to watch how it is transformed by the warmth of the Sun along its elliptical orbit
• Land a probe on a comet’s nucleus for in-situ analysis

Launch date: 2 March 2004

Mission end: 30 September 2016

Launch vehicle: Ariane-5 G+

Launch mass: Orbiter: 2900 kg (including 1670 kg propellant and 165 kg science payload); Lander (Philae): 100 kg

Dimensions: Orbiter: 2.8 × 2.1 × 2.0 m with two 14 metre long solar panels

Journey milestones

1st Earth gravity assist: 4 March 2005
Mars gravity assist: 25 February 2007
2nd Earth gravity assist: 13 November 2007
Asteroid Steins flyby: 5 September 2008
3rd 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: May - August 2014
Arrival at comet: 6 August 2014
Philae lander delivery: 12 November 2014
Closest approach to Sun: 13 August 2015
Rosetta descent to comet: 30 September 2016

Instruments

Rosetta orbiter instruments
ALICE Ultraviolet Imaging Spectrometer	OSIRIS Rosetta Orbiter Imaging System
CONSERT Comet Nucleus Sounding	ROSINA Rosetta Orbiter Spectrometer for Ion and Neutral Analysis
COSIMA Cometary Secondary Ion Mass Analyser	RPC Rosetta Plasma Consortium
GIADA Grain Impact Analyser and Dust Accumulator	RSI Radio Science Investigation
MIDAS Micro-Imaging Analysis System	VIRTIS Visible and Infrared Mapping Spectrometer
MIRO Microwave Instrument for the Rosetta Orbiter

Philae lander instruments
APXS Alpha Proton X-ray Spectrometer	MUPUS Multi-Purpose Sensor for Surface and Subsurface Science
ÇIVA / ROLIS Rosetta Lander Imaging System	ROMAP RoLand Magnetometer and Plasma Monitor
CONSERT Comet Nucleus Sounding	SD2 Sample and Distribution Device
COSAC Cometary Sampling and Composition experiment	SESAME Surface Electrical Sounding and Acoustic Monitoring Experiment
MODULUS PTOLEMY Evolved Gas Analyser

Partnerships

The orbiter's scientific payload is provided by scientific consortia from institutes across Europe and the United States. The lander is provided by a European consortium headed by the German Aerospace Research Institute (DLR). Other members of the consortium are ESA, CNES and institutes from Austria, Finland, France, Hungary, Ireland, Italy, and the United Kingdom.

Science highlights

• Discovery of how Comet 67P/Churyumov–Gerasimenko got its curious shape and insight into its double-lobed form.
• Insight into the importance of the comet’s shape in influencing its seasons, moving dust across its surface, and in explaining the variations measured in the density and composition of the coma, the comet’s ‘atmosphere’.
• The discovery of molecular oxygen and nitrogen, and water with a different ‘flavour’ to that in Earth’s oceans.
• Discovery of elements regarded as crucial for the origin of life including the amino acid glycine, which is commonly found in proteins, and phosphorus, a key component of DNA and cell membranes.
• Revelation that comets are the ancient leftovers of early Solar System formation, and not younger fragments resulting from subsequent collisions between other, larger bodies.

Mission facts

• Rosetta gets its name from the famous Rosetta stone that led to the deciphering of Egyptian hieroglyphics almost 200 years ago.
• Rosetta’s original target was comet 46P/Wirtanen, but after postponement of the initial launch a new target was set: Comet 67P/Churyumov-Gerasimenko.
• Rosetta was the first spacecraft to fly close to Jupiter’s orbit using only solar cells as its main power source.
• Rosetta is the first spacecraft to orbit a comet and land on its surface
• The Philae lander is named for the island in the river Nile on which an obelisk was found that had a bilingual inscription that enabled the hieroglyphs of the Rosetta Stone to be deciphered.