Return to Alex's
Web sources for some current
and recent planetary space missions.
This Japanese Venus orbiter was launched in 2010, failed to orbit the planet
as planned later that year, but managed to get into orbit in late 2015.
It is now studying Venus.
Akatsuki (Planet-C) homepage:
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 orbited Saturn until 2017, studying the planet, its rings and its
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. The rover is currently working its way up
the base of the huge central peak of the crater, climbing the layered rocks
Curiosity (Mars Science Lander) homepage:
DAWN: This mission
to the asteroid belt used an efficient ion propulsion system to send an
orbiter around first Vesta and then Ceres between 2011-2018. 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
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:
This joint European-Russian (ESA-RSO) mission consists of an orbiter-lander
combination that arrived at Mars in 2016. The Trace Gas Orbiter went into
orbit as planned to study the martian atmosphere, but contact was lost
with the experimental Schiaparrelli lander as it descended to the Red Planet.
ESA robotic exploration of Mars home page:
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:
Hayabusa2: This ambitious Japanese
orbiter-lander-rover mission was launched Dec 3 2014 and arrived at Ryugu,
a small (<1 km diameter) C-type near-Earth asteroid, in mid-2018. It
has dropped rovers, will fire a projectile into the asteroid, and is attempting
to collect a sample for return to Earth in 2020, including one spectacular
sampling event already.
Hayabusa2 homepage: http://global.jaxa.jp/projects/sat/hayabusa2/
InSight: This lander to the martian
equator, with the same basic design as the Phoenix lander, carries a seismometer
and heat flow probe to study the interior of Mars. The spacecraft landed
on Elysium Planitia Nov 26, 2018.
InSight homepage: https://www.nasa.gov/mission_pages/insight/main/index.html
KEPLER: This mission
to find exoplanets 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). Kepler has
found hundreds of exoplanets between 2009-2013 and again after 2016 as
part of "K2" mission, leading to a reassessment of how planetary systems
form and evolve.
JUNO: This orbiter of Jupiter arrived
in 2016 to study the gravitational and magnetic fields and atmosphere of
the solar system's largest planet, including its composition. On it's highly
elliptical polar orbit, the solar-powered spacecraft skims only 5000 km
from the cloud tops, avoiding the worst of Jupiter's strong radiation belt.
36 orbits are planned before a deorbit manuever.
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.
Spirit became stuck in sand and lost contact with Earth during the martian
winter in 2010 after power levels dropped below a threshold value. Opportunity
soldiered on but lost contact with Earth in 2018 after a major duststorm
reduced power levels below the 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
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. After completing its mission
in April 2015, MESSENGER was crashed into the planet.
MESSENGER home page:
This mission to Pluto and one or more Kuiper belt objects was launched
in January of 2006. It flew by Jupiter in March 2007 to gain speed, getting
some bonus science results. It flew through the Pluto system in July 2015,
gathering much data quickly, and Kuiper belt object KBO-2014 MU69 ("Ultima
Thule") on Jan. 1, 2019.
New Horizons homepage:
This mission to near Earth asteroid Bennu launched September 2016 and began
orbit operations in 2018 on a seven-year mission to study the asteroid
and return a sample to Earth. The mission's goals are to better understand
asteroids in general, including whether they contain organic compounds
that could have been used as a precursor to life, to refine models about
impact hazards on Earth and how to protect Earth from them, and whether
they contain useful resources.
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 provided the first extended investigation of a comet.
Launched in 2004, 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. Rosetta arrived at target comet 67P/Churyumov-Gerasimenko
in 2014, dropped a lander to the surface (Philae), and after much reconnoitering
of 67P/C-K, itself was sent to the surface of the nucleus in 2016, deactivating
just before touchdown.
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 performed a flyby of comet Tempel 1, the same comet investigated
by Deep Impact (above), in February 2011.
TESS (Transiting Exoplanet Survey Satellite):
This NASA mission uses the same transiting technique used by Kepler to
detect exoplanets but will survey a much larger region of space. Launched
in 2018, it is already finding new exoplanets.
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 April 19, 2019