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HOW TO OBSERVE THE PERSEIDS
Like eating a "Reese's Peanut Butter Cup", there are more than one way to watch the Perseids or any meteor shower. The two most popular are:
a) sit back and relax....enjoy the show!; and,
b) sit back and record your observations....enjoy the show!
For the latter, there are a few ways whereby you might actually contribute even casually to the science of "meteor wisdom" and at the same time preserve these memories via your SLR 35mm, video, or basic digital camera. Following is a quick and easy checklist and observing guide for you to enjoy and capture this celestial event .
1. KNOW THE TIME: Based on your location and the predicted times given above, don't take any chances; set your clock two hours early (the predictions might be off a bit!) and go outside prepared! Remember, for North American observers, begin your watching about 10:30 p.m. at which time there will be a few early meteors.....we never know for sure exactly when the big hit will occur. So......how about staying UP all night and use this wonderful opportunity to get acquainted with the wonders of the night sky? Note also that the Perseid Meteor Shower is known to produce many meteors as early as two weeks BEFORE and two weeks after the date of the predicted maximum!
2. KNOW WHAT TO LOOK FOR: The Perseids appear to enter the Earth's atmosphere toward the direction of the bright star Algol in the conspicuous constellation of Perseus , a constellation that appears somewhat as a "running man" (or the "keep on trucking man" to some). This "radiant" is the point at which the Earth in its eastward motion plunges into the meteoroid cloud. Use the star magnitudes (brightness's - the smaller the number, the brighter the star or meteor) given on the chart to estimate your sightings of as many meteors as possible. The naked eye can see stars as faint as about 6th magnitude on a very dark and moonless night. The constellation and radiant will rise in the eastern sky about midnight local time and will be nearly overhead (for North American viewers) near dawn.
However! It is important to note that the most meteors will NOT be seen in the direction of the radiant, but more often about 30 degrees and more away from it as the meteors are pulled deeper into the Earth's atmosphere the farther they travel. I strongly suggest that observers merely look pretty much directly OVERHEAD to see the maximum number of meteors! This "aiming rule" also applies to your camera's field of view as well.
Note that on the following Leo chart (showing only the brightest stars of the constellation) that the star magnitudes are provided, as well as the approximate location of the meteor shower "radiant." The common Arabic names of the bright stars are given for reference. The brightest star in the constellation is known as "Regulus", the "heart of the lion" while the "tail star" is that marked as "Denebola." The bright star ALGIEBA, above which the Leonids appear to radiate, is a very spectacular "double star" which is known by observers with small telescopes to appear as "...two car headlights far down a distant highway!"
Remember that the MOON hopefully should be absent during the showing of the Perseids and you should take full advantage of this opportunity; since the Perseids present meteors of all brightness levels, the darker the skies, the more meteors per hour (the "Zenith Hourly Rate," or ZHR) will be seen by each observer.
If there are several observers in your group, then orient each observer such that each is looking in a slightly different direction yet some overlap of sky coverage must occur. Each observer will count his or her own meteors beginning at about 15 minute intervals....do not combine the totals for a ZHR.....just add them up and divide by the number of observers to determine a "mean ZHR."
3. DECIDE WHERE YOU WILL OBSERVE: Be sure to plan this night carefully! Do NOT plan to observe from the city nor suburbs! Part of that planning MUST be from where you will observe to realize the darkest possible skies to see the faintest meteors.....but don't wait until that night to find a dark site. Plan to go out to your observing location on a night and time prior to the event and make sure that there are no bright "nightwatcher" lights that will interfere with your observing! If you live in a rural location it is likely that merely going into your own yard to watch the meteors will be fine; however, most "city" observers should attempt to find a very dark sky site to make the most of these relatively faint and fast meteors.
4. KNOW HOW TO OBSERVE: this is a really hard part: take out a comfortable reclining lawn chair and a blanket....position yourself with your feet toward the EAST (toward the Perseus radiant), and position yourself comfortably so that you are looking directly overhead! Such conditions are so strenuous that many, many observers have missed entire meteor showers as they nodded off in celestial bliss.
5. THINGS TO RECORD: to make the event even more meaningful, there are few minor details that you may want to record:
a) the time at 15-minute intervals and the number of meteors that EACH person sees during that short interval; this will allow you to compute for yourself and your location about when the actual peak occurs;
b) the color of the meteors; this is an indicator of both the temperature and the speed of each meteor;
c) directions of travel; although the radiant position is well known, this is an interesting exercise....merely attempt to trace your brighter meteors backwards in their pathways and you can determine for yourself via the chart above a rough idea of the radiant from your own observations!
6. PHOTOGRAPHING THE PERSEIDS: as mentioned the Perseids are fairly bright and fast for the most part; however there ARE members that will be extraordinarily bright and these can be recorded on a standard camera (35mm DSLR with a "bulb" or "time" setting), a digital camera that can allow exposures of up to 16 seconds, and a videocamera. For all types, a tripod is required and a cable release is recommended for time exposures for the still cameras. Use a fast ISO digital setting, set your lens aperture "wide open" (f1.8 or similar) and expose for at least five minutes; the stars will trail in these photographs (as you can clearly see in the 15 minute photo taken to record the bright fireball above) from the Earth's eastward rotation. With your digital camera, merely take sequences of photographs that extend as long as the time exposure setting will allow, and use the widest angle setting and aperture possible. Video camera users can capture the brightest meteors by simply "zooming out" to wide angle and allowing the camera to run continuously. Your best chances of "catching" a meteor with cameras will be through aiming the camera straight up, or alternative between that position and somewhere halfway from overhead to the southern horizon.
7. WHAT TO DO WITH YOUR OBSERVATIONS: if you catch a spectacular fireball, by all means submit your photograph to this web site! For ZHR counts and other important information that can add to the body of knowledge of our understanding of meteors and their parent comets, you can submit you records (keep a copy!) via e-mail to: http://www.imo.net/fireball/report which is the International Meteor Organization, a large world-wide group formed and continuing to add to the growing studies of meteors, comets and related phenomenon.
This is an excellent time to take the family and friends on a weekend outing into the dark and cool nights of fall. Find a quiet and restful place far from home, far from the lights and cares of the "big city," and enjoy the wonderful skies filled with the smells of impending winter, the sounds of the cold autumn blasts of artic air and the glorious sights of the winter Milky Way as it pours through constellations of antiquity. Through the bright stars of Canis Major and Orion.....across the blanket of sky that passes behind the stars of Taurus and its visitor Saturn....into the depths of Gemini and the interloping planets, our neighbors.....
....they will await you: these PERSEID meteors. This may be YOUR meteor shower of the Millennium.
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