http://www.skyandtelescope.com.au 23of its coma, and study the ‘life’ of the comet as it became
more and more active as it approached the Sun, including the
interactions of its gas and dust with the solar wind.
And to do some of that science directly on the nucleus,
Rosetta would have to successfully deliver the Philae lander
to the surface.A conjoined comet
Rosetta launched in March 2004, and after a long cruise that
included flybys of Earth, Mars and two asteroids — plus an
unnervingly long hibernation period — the spacecraft arrived
at its primary target, a periodic comet called 67P/Churyumov-
Gerasimenko, in August 2014.Flybys of comets
Year Comet name Spacecraft Distance (km)
1985 21P/Giacobini-Zinner ICE (ISEE 3) 7,860
1986 1P/Halley Giotto 596
Vega 1 8,890
Vega 2 8,030
Suisei 151,000
Sakigake 7 × 10^6
1992 26P/Grigg-Skjellerup Giot to 200
2001 19P/Borrelly Deep Space 1 2,171
2004 81P/Wild 2 Stardust 237
2005 9P/Tempel 1 Deep Impact 500
2010 103P/Hartley 2 EPOXI (DS1) 700
2011 9P/Tempel 1 Stardust 180