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The vortex,
or spin center, in this work brings
to mind satellite images of the whirling vortex in a major hurricane. In “Cyclone” tiny bubbles suspended in a
fluid are sucked in at the top, swirled down through the vortex, and released
at the bottom.
Photo Credit: NASA
A
Hurricane on Earth
In a hurricane, air flows
toward the low pressure at the center and is deflected into a spin by Coriolis
force. Coriolis force describes the
effect of the Earth’s rotation on the motion of moving objects.
This phenomenon can be
seen on all the planets in our Solar System that possess atmospheres, because all
of these planets spin. Cyclones on Mars
look much like their Earthly counterparts.
Photo Credit: NASA
A
Cyclone on the Planet Mars
In cyclones and hurricanes, airflow gains momentum as it approaches the
center of the spin, exhibiting a central principle of astronomical motion called
conservation of angular momentum. Conservation
of angular momentum (the natural law stating that the product of a spinning object’s
speed and its distance from the center of its spin must stay constant unless acted
upon by an outside force) is what accelerates the airflow in atmospheres, just
as it causes spinning figure skaters to move faster as they bring their arms
in. In hurricanes, as in figure skating,
if an object moves closer to its center of revolution, its speed must increase
to keep the product of speed and distance from changing.
The movement exhibited in
“Cyclone” is the same motion that led to the formation of the planets. The spinning primordial interstellar
cloud
that contained the material from which the Sun and its planets were formed was
huge, and more spherical than
the Solar System today. As the material
collapsed toward the center of its spin, that spin accelerated in order to keep
its angular momentum constant. Eventually the material’s spin grew to rates sufficient to place
the material into more or less stable orbit around the sun forming at the
center. The various components of the
spinning material drew ever closer together, eventually coalescing into
planets.
This
same process is observable today throughout the universe: in newly forming
stars, in spinning disks of matter being drawn into stellar black holes, at the hearts of quasars
(which possess galactic black holes), and even in the flattened spiral form of
our own Milky Way and other spiral galaxies.
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