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8-MINUTE URANUS
Named after the Greek god of the Sky
Can be visible to the naked eye, but not discovered until 1781
ROTATION/REVOLUTION/SIZE
• 7th planet – day length is 17 hrs. 14
min.
• Has an 84 year orbit
• Is one of two ‘ice giants’ –
astronomers call water, methane and
ammonia ‘ices’
• Is tilted 98º, so, seasonally is odd –
winters and summers = total dark or
light
FEATURES/MOONS
• Has two sets of rings found when
they eclipsed a distant star
• Has 27 moons – named after
Shakespeare and Alexander Pope
characters
• Miranda, imaged below Uranus to the
right, has deep caverns, and resurfaced
areas that seem new
• Aurora on Uranus are not at the
poles because its magnetic field is
tilted 60º relative to spin axis
EXPLORATION/COMPOSITION
• Only visited once in 1986 – Voyager II
• Discovered 2 new rings and 10 moons
• Discovered that the magnetic field twists like a
corkscrew behind the planet due to its orientation
and the spin of Uranus
• The planet is composed of mostly water and
ammonia in the mantle, followed by rock/metal at
the core and hydrogen, helium and methane in the
atmosphere – the methane absorbs red light,
making Uranus look blue.