Perseid Meteor Shower
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Perseid Meteor Shower 2005
The Perseid meteor shower is one of the most popular meteor showers because of when it occurs (summer in the Northern Hemisphere) and the large number of visible meteors. These two factors explain why this meteor shower attracts more non-astronomer observers than the others. The 2005 Perseid Meteor Shower will be under moonless skies, which won't occur again until 2007. The remaining major meteor showers of 2005 will be spoiled by bright moonlight, so be sure to catch the Perseids this year.
Mars will also be making an appearance during the Perseids. It will be a scant 46 degrees away in the southeast. Rising shortly after Mars and the Perseid radiant is Pleiades in the east. Around 08:00 - 09:00 UT the three will be visible.
Click here for a list of the other major meteor showers
When to Observe
2005 Perseid Peak
The peak of the Perseid Meteor shower in 2005 will be on August 12th at 18:00 UT. The peak favors the Pacific coast of Asia. Regardless of your location, it is best to observe the Perseids after midnight, preferably during the last hour before morning twilight, normally between 4:00 AM and 5:00 AM local time. Since the nearly first quarter moon will set around midnight, it will not interfere with Perseid observing. The following chart shows a sampling of locations and the time/observability at the peak.
| Location | Local Time | Observabilty/Comments |
|---|---|---|
| New York | 2:00 PM | Daytime - best to try and catch the shower in the morning of the 12th or early evening |
| Chicago | 1:00 PM | Daytime - best to try and catch the shower in the morning of the 12th or early evening |
| Pheonix | 12:00 PM | Midday - best to try and catch the shower in the morning of the 12th or early evening |
| Los Angeles | 11:00 AM | Morning - best to try and catch the shower in the morning of the 12th |
| Tokyo | 3:00 AM | Early Morning - optimal time and location |
| Moscow | 10:00 PM | Twilight - best to start at twilight and into the night |
| London | 7:00 PM | Early Evening - best to start at twilight and into the night after the peak |
Other Possible Peak 2005
Another possible increase in Perseid activity could occur near 03:00 UT, when the Earth passes close to material left behind by Comet Swift-Tuttle during an earlier pass through our inner solar system. the following table shows the time/observability of this possible peak
| Location | Local Time | Observabilty/Comments |
|---|---|---|
| Chicago | 10:00 PM | Evening - Just after evening twilight but the radiant will be at the horizon. |
| Los Angeles | 8:00 PM | Evening - start observing at twilight to try and catch some earthgrazers |
| Tokyo | 12:00 AM | Early Morning - good time and location |
| Moscow | 7:00 AM | Morning - try and observe before morning twilight |
| London | 4:00 AM | Early morning - good time to try and catch this possible extra activity |
Observing Tips
You do not need a telescope to observe a meteor shower. While you can use binoculars to try and catch the faint ones, naked eye observing will give you the widest possible field of view.
- Observe under dark skies - the maximum rate of 50 - 100 meteors per hour is based on observing the shower's peak from a dark location, with the radiant at the zenith (i.e. directly overhead). Since very few people will observe the peak under this very specific condition, a dark location is necessary to maximize the chances of seeing more meteors
- Have a blanket or sleeping bag handy - even though the days may be hot, the overnight temps cool down and an inactive body will get cold
- Sit in a reclining chair or deck chair - even a short 30 minute observing session will put a strain on your neck.
- After midnight, observe about 45 degrees altitude in the Northeast
- Observe just passed the radiant - meteors can occur in any part of the sky but the strongest activity will be close to the radiant.
Photographing the Perseids
- Use a camera that can take long exposures (30 seconds minimum; 60 seconds preferable). Note - exposures longer than 30 seconds will star to show star trails.
- Set your camera on a tripod and aim it just above any horizonal obstructions (buildings, trees, etc)
- Try to center the camera about 30 to 60 degrees from the shower's radiant
- Use the fastest ISO film or setting allowable for your camera
- Use a cable release to trigger the shutter and thus avoid shaking the camera
The image on the right is a composition of multiple 30 second exposures taken over a six hour period and combined. This Perseid Meteor shower was captured by Fred Bruenjes in 2004 using a Canon 1D Mark II using a 17-40mm F4L lense set at 17mm F4, ISO 3200, MWB 3500K, riding piggyback on an LX200. Fred Bruenjes' full-sized image: |http://www.moonglow.net/ccd/perseids.jpg
Meteor Discussion Group
You can join the new Meteor Observing discussion group to ask questions and/or share your experiences. This is a great place to discussions meteors, meteor showers and fireballs.
Background
While history of the Perseid meteor shower can be traced back to 36 AD, the first observer to record a count of the shower was Eduard Heis, a german astronomer, who recorded 160 meteors per hour in 1839. Heis had exceptionally good eyesight and opted to do naked eye observations. He studied the Milky Way, the zodiacal light, and of course, shooting-stars.
The orbit of the Perseids were computed by Giovanni Virginio Schiaparelli, an Italian astronomer, between 1864 and 1866 brought to light a resemblance to the comet Swift-Tuttle. This was the first time a meteor shower was positively identified as a result of a comet. The higher Perseid rates of 1861-1863 were directly due to the appearance of Swift-Tuttle, which was calculated to have a period of about 120 years (revised later).
By studying meteor streams over the years, astronomers have been able to conclude that meteorids, small particles about the size of a grain of sand, orbit the sun and were produced by comets. As the Earth passes thru the orbit of a comet it encounters these meteorids, and the friction between a high-velocity meteorid and the air molecules causing it to vaporize. These particles and the in the atmosphere collide and are stripped of electrons creating the strong illuminosity we see, providing us with natural fireworks.
In 1980, minor searches for comet Swift-Tuttle began and more rigorous searches were conducted in 1981 and 1982 but nothing was found. Tsuruhiko Kiuchi discovered a comet in September 1992 which was identified as Swift-Tuttle. The comet was last seen by observers at the Siding Spring Observatory in Australia in March 1995. Click here to see the simulated orbit of comet Swift-Tuttle.
Comets are time capsules that hold clues about the formation and evolution of the solar system. They are composed of ice, gas and dust, which is the primitive debris from the solar system's earliest and coldest formation period - 4.5 billion years ago. Deep Impact, a NASA Discovery Mission, is the first space mission to probe beneath the surface of a comet and reveal the secrets of its interior.
In January 2005 NASA launched Deep Impact, a space craft with an impactor, for a rendezvous with Comet Tempel 1 (discovered in 1867 by Ernst Tempel). In early July 2005, 24 hours before impact, the flyby spacecraft pointed it's high-precision tracking telescopes at the comet and released the impactor on a course to hit the comet's sunlit side. The impactor was a battery-powered spacecraft that operates independently of the flyby spacecraft for just one day. The impactor had its own navigation system to maneuver into the path of the comet. Cameras on the Deep Impact spacecraft and the impactor captured and relayed images of the comet before, during and after the collision. The impact was not forceful enough to make an appreciable change in the comet's orbital path around the Sun.
More information on the Perseid Meteor Show from the American Meteor Society
