Observing meteors and meteor showers is a great way to start observational astronomy. Because it
requires no telescope or other optical aid, it's an astronomical activity that almost anyone can enjoy. All you need
are your eyes, a comfortable lawn chair, clear and reasonably dark skies, and a blanket if it's cold.
Meteors are pieces of space debris, usually left by a comet as it orbits our Sun. Although meteors can be
large, the typical size of the particle that produces such a lovely display in our sky ranges from about the size of a
grain of sand to the size of a small pebble. These particles burn up in our atmosphere before reaching the ground. Most
meteors may be tiny, but because they hit our atmosphere with great velocity, they glow brightly as they burn up and
thus we are able to see them. Although some meteors can be seen from urban skies, many meteors will only be visible under
dark country skies. As you might expect, a bright moon can hamper observing from dark sky sites. Fortunately, the dates
of full moons change from year to year, so if a bright moon ruins a particular meteor shower in one year, it can be
observed during a dim or new moon in other years.
On any clear night, some meteors can be seen. These meteors, termed sporadic meteors, are not
associated with any particular meteor shower and from a dark sky site you may see up to 20 or more of these on just
about any night. Meteor showers are heavier displays that recur from year to year. The number of meteors
visible depends upon the shower, but the number of visible meteors can range from 5 per hour to 100 per hour
or more.
While sporadic meteors appear to come from random directions in the sky, a meteor shower has a radiant.
The radiant of a shower is the point in the sky from which meteors would appear to come if you traced their visible paths
backward. Like sporadic meteors, meteors from a shower can be seen in any part of the sky, but if you take the ending
point of the meteors' trails and trace them backward through their starting points, the place where these paths converge
is the radiant for that shower.
Most meteor showers are at their best after midnight. After midnight, you're on the leading edge of the Earth and you're
meeting the meteors head on. Before midnight, you're on the trailing edge of the Earth and the meteors have to catch up to
you. As a result not only are more meteors seen in the pre-dawn hours, but their impact speeds encountering the Earth's atmosphere are much higher and the meteors are generally faster and brighter.
I have created a low volume email list for advance notification of upcoming meteor showers and unusual astronomical events; especially those that can be observed with the unaided eye, binoculars, or a small telescope. To join, simply enter your email address below and click on the join now button.
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