Two horses, the sun and the moon...

In Norse mythology, Árvakr ('early awake') and
Alsviðr ('very quick') are the horses which pull the
sun, or Sol's chariot, across the sky each day

The Sun (Sól) with the horses Árvakr and Alsviðr and
the Moon (Máni) Hjúki and Bil, 1909 by J. C. Dollman
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Hjúki (possibly meaning 'the one returning to health')
and Bil (Old Norse) are a brother and sister pair of
children who follow the personified moon, Máni,
across the heavens.

'The Chariot of the Sun', 1908 by W. G. Collingwood,

The chariot of the sun being pursued by wolves
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'Far away and long ago', 1920 by Willy Pogany

An illustration by Willy Pogany from a chapter from
'Children of Odin' entitled 'How Loki wrought mischief
on Asgard'. No title otherwise given for the work. The
wolf Sköll chases the personified sun, Sól, and his brother
Hati Hróðvitnisson chases the personified moon, Máni
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A depiction of Máni and Sól, 1895 by Lorenz Frølich
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