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iconic images of Io transiting
Jupiter. Voyager 2 also got a closer
look at Europa, showing that it
was covered in a crust of water
ice riven by cracks. Later analysis
revealed that these cracks were
caused by upwellings in a liquid
ocean under the crust, an ocean
that is estimated to hold at least
twice as much water as Earth and
which is thought by scientists
to be a prime candidate for the
presence of alien life.
Titan and Saturn
By November 12, 1980, Voyager 1
was skimming 77,000 miles
(124,000 km) above the atmosphere
of Saturn. On the approach, and
despite some instrument failures,
it revealed details of the rings,
which were made of billions of
chunks of water ice and were
as thin as 30 ft (10 m) in places.
Kohlhase had sent Voyager 1 to
visit Titan before approaching
Saturn to prevent any damage
caused by Saturn’s atmosphere
and rings from endangering this
crucial phase. The spacecraft
swung behind Titan so the sun’s
light shone through the atmosphere,
allowing measurements of its
thickness and composition.EXPLORING THE SOLAR SYSTEM
The Titan trajectory then sent
the craft over Saturn’s pole
and away to the edge of the
solar system.
Voyager 2 arrived at Saturn
in August 1981, and was able
to study the planet’s rings and
atmosphere in more detail, but
its camera failed during much
of the flyby. Fortunately, it was
restored, and the order was given
to continue to the ice giants.Uranus and Neptune
Voyager 2 is the only craft
to have visited the ice giants
Uranus and Neptune. It took 4.5
years to travel from Saturn to
Uranus, where the craft passed
50,500 miles (81,500 km) above
the pale blue atmosphere. It
looked at the planet’s thin rings
and discovered 11 new moons,
all of which are now named after
Shakespearian characters, as
is the rule for Uranus. The most
curious thing to be examinedCharles Kohlhase
Charles “Charley” Kohlhase
was born in Knoxville,
Tennessee, and graduated with
a degree in physics. He briefly
served in the US Navy before
joining JPL in 1960, where he
turned his life-long fascination
with exploration into work on
the Mariner and Viking projects,
before joining the Voyager team.
In 1997, Kohlhase left Voyager
to design the Cassini–Huygens
mission to Saturn, which
succeeded in dropping a lander
onto the surface of Titan in- In the late 1970s, he
worked with computer artists
to create accurate animations
of space missions for advancing
the public understanding of
NASA’s work. Now retired,
Kohlhase remains involved in
several projects that blend art
and space science, aiming to
educate and inspire the next
generation of rocket scientists
and interplanetary explorers.
Key work1989 The Voyager Neptune
travel guideVoyager 2 sent back this image of
Neptune’s ice moon Triton. During the
craft’s flyby, only the southern ice cap
was visible. Highly reflective, it is
made of frozen nitrogen and methane.