Return to Alex's
Web sources for some current
and recent planetary space missions.
CASSINI: After nearly seven years
of interplanetary travel, the Cassini spacecraft went into orbit around
Saturn for a multi-year mission on July 1 of 2004. Seven months later it
dropped the Huygens probe built by the European Space Agency, which made
the first-ever landing on the big mystery moon Titan. Cassini has
been studying the planet, its rings and its moons, and recently detected
ongoing volcanic activity on the small moon Enceladus. The large
moon Titan, which appears to have an active methane hydrology, will be
a continuing focus of the orbiter which is now in an extended mission.
CURIOSITY: The largest rover yet
to land on Mars began exploration August 2012 in the huge Gale Crater armed
with a battery of innovative scientific equipment. This NASA mission
didn't take long to make the discovery that conglomerate is present on
the crater floor, which requires sustained and active water-mediated erosion
and deposition. Plans are for the rover to eventually make its way
to the huge central peak of the crater and begin climbing the layered rocks
Curiosity (Mars Science Lander) homepage:
DAWN: This mission to the asteroid
belt uses an efficient ion propulsion system to send an orbiter around
Vesta in 2011 for about 11 months and around Ceres in 2015 for about 5
months. The new ion propulsion system allows the possibility of multiple
orbit targets. Vesta and Ceres are the third largest and largest
asteroids respectively but are very different: Ceres is icy and has a relatively
dark surface; Vesta is dry, has basaltic and other igneous rocks on the
surface, and is relatively bright.
DEEP IMPACT: It sounds like
a movie, but actually the hollywood folks stole this name from a real NASA
mission. On July 4, 2005, part of the DI probe rammed at high velocity
into comet Tempel 1, while the other part flew by to observe and analyze
the pyrotechnics. This mission provided a good experiment to
try to understand what comets are made of. In case you are wondering,
the July 4 impact date had everything to do with the holiday of the nation
that funded this mission.
Deep Impact home page:
The DI flyby spacecraft was repurposed
for a flyby of comet Hartley 2 (which occurred in November, 2010) and for
observations of some transiting extrasolar planets. The mission was
EPOXI home page:
GRAIL: Two spacecraft- named Ebb
and Flow-- flew in formation around the Moon in 2012 and precisely measured
small changes in velocity between them. This provided information
about the gravity field of, and mass distribution within, the Moon.
Additional images are available at:
KEPLER: This mission to find explanets
uses a photometer to search for variations in light emissions of stars
that are experiencing planetary transits (planets moving in front of the
disk of the star and dimming the light). It was launched March. 6,
2009 for an anticipated 4 year mission. Kepler is capable of finding
"terrestrial mass" planets.
LUNAR RECONNAISANCE ORBITER: This
orbiter launched in June 2009 to obtain high-resolution images and to map
the topography, temperature, and H content of the lunar surface.
A companion spacecraft, LCROSS, crashed into a shadowed area near the south
pole of the moon in October 2009, kicking up a plume that confirmed the
presence of water ice there.
LRO image gallery:
MARS EXPLORATION ROVERS: In January
of 2004, twin rovers touched down at separate equatorial locations on Mars
to search for signs of liquid water activity in Mars' distant past.
Opportunity is still operational, but Spirit became stuck in sand and lost
contact with Earth during the martian winter after power levels dropped
below a threshold value.
Raw image postings (there are some gems
here, but you have to sift through tens of thousands of images to find
MARS EXPRESS: The European Space
Agency in December of 2003 inserted a spacecraft in orbit around Mars.
Just before reaching Mars, it dropped a small British lander called the
Beagle 2, which was never heard from again. Meanwhile, the orbiter
is completely functional and returning much useful data.
Mars Express home page:
MARS ODYSSEY: This NASA orbiter
reached Mars in October, 2001. It has finished its primary mission,
but is continuing to chemically map the surface and finding lots of subsurface
water ice. The MO orbiter has also served as the main communication
relay to the MER rovers.
Mars Odyssey homepage:
Images can be viewed at:
MARS RECONNAISSANCE ORBITER:
This latest of a series of NASA missions to Mars arrived at the Red Planet
in 2006. It has the highest-resolution imager ever sent into
Mars' orbit, sufficient to discern boulders or landers on the surface and
to directly characterize the roughness of potential landing sites.
On-line image viewer for high-resolution
MESSENGER: This NASA spacecraft
went into orbit around Mercury in March 2011. But to slow down sufficiently,
MESSENGER had to first flyby Earth once, Venus twice, and Mercury three
times. MESSENGER is only our second spacecraft visit to Mercury,
after Mariner 10 in the 1970s.
MESSENGER home page:
NEW HORIZONS: This mission
to Pluto and one or more Kuiper belt objects was launched in January of
2006. Although it will take many years to reach its destinations
(July 2015 for a fast Pluto system encounter), it flew by Jupiter in March
2007 to gain speed, getting some bonus science results.
New Horizons homepage:
PHOENIX: This mission to the martian
arctic (latitude 68 N) followed in the footsteps of the Mars Polar Lander,
which crashed on Mars in 1999, and the Mars 2001 Surveyor, which was cancelled.
This time the mission proceeded to a successful landing in 2008.
Phoenix dug into the subsurface and analyzed the chemical, physical, and
thermal properties of the confirmed icy soil. Included among the instrument
suite were optical and atomic force microscopes that imaged collected
soil at unprecedented small scales.
Phoenix NASA missions homepage:
Phoenix University of Arizona homepage:
ROSETTA: This European Space Agency
mission will provide the first extended investigation of a comet.
Launched in 2004, Rosetta will arrive at target comet 67P/Churyumov-Gerasimenko
in 2014 and orbit the comet for two years and drop a lander onto the surface.
Along the way, Rosetta flew by Earth 3 times and Mars 1 time to gain speed,
and to obtain bonus science it flew by asteroid Steins in September 2008
and Lutetia in July 2010.
STARDUST: On Jan. 2 of 2004 the
Stardust spacecraft flew through the cloud of dust and gas surrounding
comet Wild 2, collecting particles which were returned to Earth in January,
2006. As planned, only tiny bits of material were returned, but that's
all we need to learn a lot about what comets are made of. Stardust
was the first space mission to retieve extraterrestrial material from a
planetary body since 1976, when a russian lander brought back soil from
the moon. Research continues on the material that has been returned.
Stardust home page:
STARDUST-NEXT: The carrier spacecraft
for Stardust is now enroute for a flyby of comet Tempel 1, the same comet
investigated by Deep Impact (above). The flyby is scheduled for February,
VENUS EXPRESS: Following
in the footsteps of Mars Express, this European Space Agency (ESA) spacecraft
went into orbit around Venus in 2006. It has instruments for
measuring the magnetic field and plasma environment around Venus, spectrometers
for measuring the temperature and composition of the atmosphere, and a
multispectral camera for studying cloud structures.
Venus Express homepage:
Venus Express images:
Page last updated March 7, 2013