884 Encyclopedia of the Solar System
FIGURE 10 The NASA spacecraft
Near-Shoemakerwas launched in 1996.Venus section). (See http://www.planetary.org/html/neo/Missions-
Research/index.html.)
Galileo En Route Encounters
While en route to Jupiter on its long journey with grav-
ity assists at Venus and Earth, the NASAGalileospace-
craft flew by two asteroids, 951 Gaspra in 1991 and 243
Ida in 1993, and obtained close-up imagery, spectra, and
other measurements. A highlight of the Ida encounter was
the discovery of the tiny moon Dactyl orbiting Ida. (See
galileo.jpl.nasa.gov/facts.htm.)
NEAR-Shoemaker
Launched in 1996, the NASA spacecraftNear-Shoemaker
entered orbit about asteroid 433 Eros in 2000, delivered
imagery, spectrometric data, and gravitometric data. After
one year in orbit it was commanded to a gentle touchdown,
which it survived, even though not designed for landing
(Fig. 10). (See near.jhuapl.edu/.)
Deep Space 1
The NASA craftDeep Space 1launched in 1998 to demon-
strate solar-electric propulsion, autonomous navigation,
and other new technologies, encountered asteroid 9969
Braille in 1999, though it only returned a few distant, low-
resolution images. Its mission was extended to a close flyby
of Comet Borrelly on 22 September 2001 and successfully
imaged the nucleus at visible and infrared wavelengths. (See
nmp.jpl.nasa.gov/ds1/.)Stardust
With the goal of collecting samples of cometary dust and re-
turning them to Earth, NASA’sStardustmission, launched
in 1999, flew by asteroid 5535 Annefrank in 2002, and
encountered Comet Wild 2 in 2004, returning imaging
data. The sample return capsule successfully parachuted to
Earth on January 4, 2006, with its precious cargo of thou-
sands of cometary (and interstellar) dust particles. (See star-
dust.jpl.nasa.gov/top.html.)Hayabusa (Muses-C)
An ISAS mission with assistance from NASA,Hayabusa
was launched in 2003 and used solar electric propulsion
to rendezvous with asteroid 25143 Itokawa in Septem-
ber 2005. It returned multispectral imaging and grav-
ity data and attempted to collect surface samples for
return to Earth. The spacecraft is en route to Earth but
technical problems have delayed arrival until 2010. (See
http://www.isas.jaxa.jp/e/enterp/missions/hayabusa/index.html.)Rosetta
Rosetta, an ESA mission launched in March 2004 with an
Ariane V, is scheduled to arrive at Comet Churyumov-
Gerasimenko in 2014 after three Earth gravity assists and