May Sky: Clock of the Gods
Saturn, visible all night this
month, is among the most beautiful of planets. But ancient observers saw it as
a symbol of mortality.
By Corey S. Powell of Discover Magazine
With its jewel-like rings and golden
hue, Saturn is the most beautiful of the planets — perhaps the most
iconic object in all of science. Now is the ideal time to see the ringed
planet, as it rises just before sunset and stays visible all night.
A view through even a modest
telescope elicits gasps of disbelief: Yes, it really looks like that. It is
easy to find — just look to the southeast a few hours after twilight. Saturn
hovers about one-third of the way from blue-white Spica (the brightest star in
Virgo) on your right to ruddy Antares (the star at the heart of Scorpius, the
scorpion) on your far left.
Saturn is also, less famously, an
icon of mortality. It takes 29.5 years to complete one orbit around the sun and
one circle through Earth’s sky, by far the slowest motion of any naked-eye
planet. Perhaps that is why the Roman god Saturn was associated not only with
Cronus (his Greek equivalent) but also the phonetically similar Chronos (the
personification of time).
You can measure the epochs of your
life by Saturn’s shifting position. If you are young and vigorous now, you
might see it two more times in the same part of the sky near Spica. If you see
it there a third time, you will be among the oldest people on the planet.
Nobody alive today will witness Saturn’s fourth lap.
The entire post can be found at: http://discovermagazine.com/2013/may/18-may-sky-clock-of-the-gods
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