Mercury (element) in Space
I know that in space water forms a ball as mercury does on earth and
I wondered what happens to mercury in space.?
Generally it will form a ball. In empty space there would be no
forces on the mercury other than the internal forces between mercury atoms.
They attract one another weakly (by "van der Waals forces" and by gravity), and
so the mercury will pull itself into the most compact possible shape, which
is a sphere, if the mercury is not rotating (if it is, the most compact
possible shape would typically be a flattened sphere, like a beach ball
when you sit on it). Space is not ever really empty, mind you, and under
many circumstances the mercury will assume other shapes. If the mercury
were in orbit around another body, for example, there would be tides on the
mercury ball much like the tides that occur in the Earth's oceans because
of the nearby presence of the Moon, and the mercury would be egg-shaped.
A sphere is the equilibrium and thus ultimate shape, generally, but the
shape at any given time would also depend on the history of the mercury.
How much is there? Where did it come from? How hot was it then? How long
has it been in space? If, for example, you dumped only a gram or two of roo
temperature mercury out your space-station window, it might well all evaporate
right away, or, if not, it could take longer than the present age of the
Universe to relax from an initial irregular "splash" shape to a tiny sphere.
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Update: June 2012