A beginner generally finds great difficulty in locating the beginning
and ending of the course of a meteor, as these seldom occur close to any
well-known star. It will always be found useful to have a straight rod
about four feet long. This should be held up so that it seems to lie
along the path of the meteor. A rapid glance along the rod, backward and
forward, will generally be sufficient to enable one to detect some stars
within the radius of a circle. The beginning and ending of the trail of
the meteors can then be recorded, as the eye easily estimates the length
of the arc between various points of the heavens. In this way one
records the observation made—let us say, at 4.39, for November 15, 1899.
The direction followed by the meteor was from the radiant toward Castor
and Pollux, the streak remaining visible for three seconds. The meteor
was very bright, meaning that it equaled a first-magnitude star, and the
train was 5° in length. Though the color was not recorded at the time,
yet it is possible to make a very sure guess, that it was blue, the
usual color of Leonids.
It is not advisable to look for meteors very far from the radiant, as
that is the main point from which they are seen to emanate. Therefore,
it will be sufficient to confine the attention to a region within 30° to
40° from the radiant. Meteors appearing near the radiant have short
trains, while those at a greater distance have generally longer trains.
When a meteor is observed, the time, magnitude, beginning and ending of
course, duration of flight, and any special characteristics should be
recorded as quickly as possible, using a system of abbreviations.
Possibly the writer, at the next display which is expected in 1933, may
be prepared—with the assistance of a few enthusiasts—to carry out this
elaborate program, but it is impossible for one or even three to make an
accurate record of so many happenings regarding a meteor which may have
remained on view but a second or so.
In judging the time of flight a stop-watch is very useful, but in
the case of slow meteors it is easy to estimate the time
approximately by counting at a certain rate, say 180 to the minute.
The writer was told to recite a nursery rhyme at a certain pace,
such as hickory-dickory-dock, and note the syllable or word uttered
at disappearance of meteor, but in the case of the Leonids the word
“hickory” had scarcely been uttered before the Leonid had vanished,
so that the simpler method of counting “one, two, three,” was
adopted, proving entirely satisfactory, when we remembered to count!
Public-domain text, read in full here on John Shaqi.
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