Rosetta Spacecraft


Rosetta Spacecraft is a comet explorer that will land on a comet (Churyumov-Gerasimenko) and study its composition of the comet. Data may provide an insight into the origins of our solar system. Rosetta spacecraft was launched on 2nd March 2004 by an Ariane 5G rocket from Kourou, French Guiana.

Rosetta Spacecraft Picture

What is Rosetta?

Rosetta is a European Space Agency (ESA) mission. The Rosetta spacecraft will take 10 years to reach its target destination Comet 67P/Churyumov-Gerasimenko. The probe will orbit the icy nucleus and release a small lander onto its surface. The cometary mission takes its name from the Rosetta stone, which was the key that unlocked the secrets of ancient Egyptian hieroglyphs.

European Space Operations Centre  in Darmstadt, Germany  will control the Rosetta spacecraft operations. ESA’s 35 m ground station in New Norcia, near Perth, West Australia will relay spacecraft data.

The Rosetta Mission:

The following is a summary of the various phases of the mission:

– First Earth gravity assist – March 2005

– Mars gravity assist – March 2007

– Second Earth gravity assist – November 2007

– Rosetta will fly by the asteroid Steins on 5 September 2008 at a distance of just over 1700 kilometres. This encounter will be the first excursion into the asteroid belt by Rosetta.

– Third Earth gravity assist – November 2009

– Rosetta will fly by asteroid Lutetia on 10 July 2010 within about 3000 kilometres. This will be the second encounter of the asteroid belt.

– Enter hibernation – July 2011

– Exit hibernation – January 2014

– Rendezvous manoeuvre – May 2014

– Global Mapping – August 2014

– Philae Lander delivery – November 2014

– The mission ends – December 2015

* To gain enough orbital energy to reach its target, one Mars and three Earth gravity assists will be required.

Rosetta Spacecraft Specifications

Total Launch Mass: 3,000 kg
Propellant: 1,670kg
Philae Comet Lander: 100kg
Main Structure: 2.8 x 2.1 x 2.0 metres
Diameter of solar arrays: 32 metres


The Rosetta mission was approved in November 1993. Originally Rosetta was going to be launched in January 2003 by an Ariane 5 ESC rocket. However due to the failure of the first Ariane ESC rocket, the launch was postponed. The comet target would have been Comet Wirtanen. Rosetta will rendezvous with a new comet target, Churyumov-Gerasimenko in 2011.

On 11 March 2004, the Rosetta Science Working Team selected the asteroids Steins and Lutetia to fly by during Rosetta’s journey to Comet 67P/Churyumov-Gerasimenko.

Rosetta Lander

Rosetta lander is called Philae. It is box shaped and weighs 100 kg. The landing will happen in November 2014. If it is successful, Philae Lander will be the first spacecraft ever to make a soft landing on the surface of a comet nucleus.

Rosetta Lander

What does Philae mean?

Philae is the island in the river Nile on which an obelisk was found that had a bilingual inscription including the names of Cleopatra and Ptolemy in Egyptian hieroglyphs. This provided the French historian Jean-François Champollion with the final clues that enabled him to decipher the hieroglyphs of the Rosetta Stone and unlock the secrets of the civilisation of ancient Egypt.

About Steins and Lutetia

Steins and Lutetia lie in the asteroid belt between the orbits of Mars and Jupiter.

Asteroid Steins Asteroid 2867 Steins was discovered on 4 November 1969 by N. Chernykh.  It is roughly 10 km in diameter.

The asteriod Lutetia was discovered on 15 November 1852 by H. Goldsmith. It is roughly 100 km in diameter. It is a much larger than Steins.

Related Books:

Riddle of the Rosetta Stone: Key to Ancient Egypt by James Cross Giblin

Planet Quest: The Epic Discovery of Alien Solar Systems by Ken Croswell

Distant Wanderers: The Search for Planets Beyond the Solar System by Bruce Dorminey


Rosetta Spacecraft Links and References:

ESA – Rosetta Mission

Asteroid 2867 Steins

Occultations by (2867) Steins

Picture Source of spacecraft and lander: ESA – Rosetta Mission

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