Greetings:
Last night at around 11:20 pm,
August 12, 2009, Melanie and I drove over to the
shore of Lake Erie and set up our camping chairs
to watch the Perseid meteor shower. In case you
do not know, the name comes from the fact that the
radiant point of the meteors is located in the constellation
of Perseus. A little farther to the celestial north
and they would have been called the Cassiopeian
meteors. These meteors are caused by the Earth passing
through the debris from the Swift-Tuttle comet.
Here is "Sky & Telescope" magazine's illustrations
of the radiant point:
The place to look for the meteors is not necessarily
in the direction of the radiant. In fact, most of
the Perseid meteors we saw last night ran in a 60-degree
pie slice that originated in Perseus and was centered
on the Milky Way, passing through Cygnus and on
down toward the horizon to Sagittarius. The sky
was lit fairly brightly because of the light of
the city of Erie to the east, and the marina to
the west, but the nearest city to the north is in
Canada so no light there, and there is no large
city to the south of our observing point.
Many of the brightest meteors we witnessed were
over toward Venus, in the constellation of Gemini.
The best one we saw was nearly in the fireball category
as it produced a long, bright vapor trail for 20-30
degrees. It was awesome and almost spooky to see
such a violent event without any sound. That meteor
occurred around 11:30 pm and ran through the constellation
of Boötes. I did not get any photographs of the
meteors.
However, I did get a couple really
cool photos of the moon and Venus. The moon was
in a waning gibbous stage, just a day away from
last quarter. In the picture below, you can clearly
see the craters along the terminator. The moon was
in the constellation of Aries. Photos were taken
with my Canon S2 IS Power Shot camera on a tripod.
These two pictures of Venus were taken
just a minute or two apart. Notice how far Venus
has shifted relative to the background stars in
the constellation of Gemini (it is in prograde motion
now). Note that Venus is nearly full at this time
(slight darkening of the western edge); it exhibits
phases as it orbits the sun just like the moon does
as it orbits the earth. Mercury shows phases as
well since it is also an inferior planet (orbit
between the Earth and the sun). Superior planets
do not exhibit phases.
We have been experiencing a "year without a
summer" here in Erie, with very few days ever getting
above 80 degrees. The nights are in the upper 50s
and lower 60s. Here is how Melanie braved the cool
night air... she didn't appreciate the camera flash.
If you have Perseid meteor photos that
you would like to have added, please e-mail them
to me and I'll be glad to post them.
