Philips Atlas of the Universe

THE SOLAR SYSTEM

▲ The cratered surface

of Mercury. This is also

an image from Mariner 10.

The most obvious difference

between Mercury and the

Moon is that Mercury lacks

broad plains similar to the

lunar maria.

 The magnetosphere

of Mercury. The discovery

of a Mercurian magnetic

field was something of a

surprise. No radiation belts

can form, but there is a

definite interaction between

the Mercurian field and

the solar wind; there is a

well-defined bow-shock.

The presence of a magnetic

field is certainly due to the

comparatively large iron-rich

core of the planet.

Mercury from Mariner 10.

Six hours after its closest

approach, Mariner 10 took

this series of 18 images of

Mercury’s surface, which

have been combined to

make a photomosaic.

Note that, in general, the

arrangement of the craters

follows the lunar pattern;

small craters break into

larger ones, not vice versa.

There are also ray centres.

The north pole is at the top.

Magnetopause

Magnetotail

Solar wind

Bow shock

3

3

RM

RM

2

2

4 5 6 7

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