— Ch. 1 · Mission Genesis And Development —
Rosetta (spacecraft).
~5 min read · Ch. 1 of 7
The European Space Agency launched the Rosetta probe on the 2nd of March 2004 from the Guiana Space Centre in Kourou, French Guiana. This mission began as a cooperative effort between ESA and NASA to study comets following the success of the Giotto probe during Halley's Comet approach in 1986. The original plan involved a sample return mission called CNSR that would share design elements with NASA's CRAF project. Budget constraints forced both agencies to cancel their respective programs by 1993. ESA then redesigned the mission to include an asteroid flyby followed by a comet rendezvous with an attached lander. Gerhard Schwehm served as mission manager after launch until his retirement in March 2014. The total cost reached approximately €1.3 billion (US$1.8 billion). A new target comet named 67P/Churyumov, Gerasimenko was selected in May 2003 after an Ariane rocket failure delayed the initial January 2003 launch date. Two co-discoverers of the comet, Klim Churyumov and Svetlana Gerasimenko, attended the actual launch event.
The Long Journey To The Comet
Rosetta used gravity assist maneuvers to accelerate through the inner Solar System over its twelve-year journey. The spacecraft performed three Earth flybys on dates including the 4th of March 2005 and the 13th of November 2007. A risky Mars flyby occurred on the 25th of February 2007 at an altitude of just 250 kilometers. During this encounter, solar panels could not generate power because the craft entered the planet's shadow for fifteen minutes. Engineers nicknamed this maneuver "The Billion Euro Gamble" due to the danger of running out of battery power. Rosetta also visited two asteroids: 2867 Šteins in September 2008 and 21 Lutetia in July 2010. The mission included a record-setting hibernation period lasting thirty-one months from June 2011 until January 2014. All electronics except the onboard computer and hibernation heaters were switched off during this deep space phase. Reaction wheel failures required complex troubleshooting before the spacecraft could resume operations near the comet.