BBC Sky at Night - UK (2021-08)

64 BBC Sky at Night Magazine August 2021

Þ Jupiter’s southern

aurora is barely

visible from Earth,

because of our

planet’s position in

respect to the gas

giant’s south pole

Missions after Juno

The next set of Jupiter missions will focus not on the planet, but its moons

The liquid water oceans of

Jupiter’s icy moons have long held

a fascination for planetary

scientists, partly for what they can

teach us about water in our Solar

System and partly because of the

tantalising possibility that they

might provide havens for life. Now

three planned missions will turn

their focus on these icy worlds.

First to launch in June 2022 will

be the European Space Agency’s

(ESA’s) Jupiter Icy Moons Explorer

(JUICE) looking at Jupiter’s moons

Ganymede, Callisto and Europa.

After arriving at the gas giant in

2029, JUICE will spend the first

few years orbiting Jupiter,

performing flybys of the moons to

map out their surfaces visually,

while using radar to peer beneath.

Finally, in 2032, JUICE will start

orbiting Ganymede, the largest

moon in the Solar System.

Next up is NASA’s Europa

Clipper, which is set to launch in

October 2024. Previous missions

have spotted water plumes

erupting from Europa’s surface,

potentially providing a way to get

a close-up of the water on the

moon without having to drill

through 20km of ice to reach it.

Finally, the Chinese National

Space Administration (CNSA) is

planning the Gan De probe. The

launch is pencilled in for 2029,

arriving at Jupiter in 2035, though

exactly what it will do there is still

being decided. One option is to

send it to Callisto, completing the

trio of icy moon examinations.

Alternately, it could end up visiting

the highly volcanic Io and perhaps

even sending a lander to the

surface. Whatever happens, it

looks like Jupiter’s moons should

prepare for visitors.

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> Top: the Europa Clipper will look

for water on its namesake moon

Below: Jupiter Icy Moons Explorer

(JUICE) will map the surfaces of

Ganymede, Callisto and Europa IL

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