SMITHSONIAN

CONTRIBUTIONS

to

ASTROPHYSICS

Smithsonian Institution

Astrophysical Observatory

Volume 8, Number 6

Second Catalog of

Hourly Meteor Rates

By Charles P. Olivier

Washington, D. C.

Smithsonian

Contributions to Astrophysics

VOLUME 8, NUMBER 6

SECOND CATALOG

OF HOURLY METEOR RATES

by CHARLES P. OLIVIER

SMITHSONIAN INSTITUTION

Washington, D.C.

1965
Publications of the Astrophysical Observatory

This series, Smithsonian Contributions to Astrophysics, was inaugurated

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solar system. Its pages are open to a limited number of paiK'rs by other

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Another series is Annals of the Astrophysical Observatory. It was started

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been published about every 10 years since that date. These quarto volumes,

some of which are still available, record the history of the Observatory's

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Many technical papers and volumes emanating from the Astrophysical

Observatory have appeared in the Smithsonian Miscellaneous Collections.

Among these are Smithsonian Physical Tables, Smithsonian Meteorological

Tables, and World Weather Records.

Additional information concerning these publications may be secured from

the Editorial and Publications Division, Smithsonian Institution, Washington, D.C.

FRED L. WHIPPLE, Director,

Astrophysical Observatory,

Smithsonian Institution.

Cambridge, Mass.

For sale by the Superintendent of Documents, U.S. Government Printing Office

Washington. D.C. 20402 - Price 20 cents
Second Catalog of Hourly Meteor Rates

Charles P. Olivier

 l

The first catalog of hourly meteor rates

(Olivier 1960) contained data collected by the

American Meteor Society for the interval

1901 to 1958. For brevity, this earlier catalog

will be referred to in this contribution as K3,

the present one as K4. This latter contains

data for the interval 1958 to 1963 inclusive; it

also includes some material for 1964 which

arrived in time for inclusion, as well as a

considerable amount obtained earlier than 1958

which, for a variety of reasons, was not used in

K3 (see references).

While the existence of the data given here

has been mentioned in some detail in the Annual

Reports of the American Meteor Society (AMS)

few if any hourly rates have been published.

However, thanks to the kindness of Professor

Kojiro Komaki of the Kanaya Observatory,

Japan, and Chairman of the Japanese Meteor

Committee, who also has been a valued AMS

member for several decades, the annual provisional reports from Japan have been made

available. These do give, in most cases, the

corrected hourly meteor rates. The Japanese

meteor observers in recent years have done an

immense amount of work, and their observations probably account for between 30 and 40

percent of all the rates used as the basis of this

paper. Hence this catalog is based almost

entirely on work done in the United States and

Japan. Less than one percent came from the

Southern Hemisphere and Europe.

In addition to members of the AMS, contributors in the United States include scores of

others who occasionally observed, particularly

on the dates of the chief annual showers. A

few reports from ships, made on these dates,

are available also. Copies of some reports

made by persons working on the meteor program for the International Geophysical Year

were sent in. The tables follow exactly the

1

 Flower and Cook Observatory, University of Pennsylvania,

Philadelphia.

same form as in the K3. They summarize all

observations available in our files and not used

in K3, with the exception of certain material

which was omitted:

1. Great efforts were made to have as many

nonmembers as possible observe during the

Perseid epoch, particularly from 1929 to 1934.

Hence tens of thousands of meteors were reported, seen mostly from August 9 to 13

inclusive, and the records are available. The

observations used in these tables represent

primarily those considered superior, for any

reason, and quite typical of the whole. Thousands were omitted. However, much material

not used in K3 was entered in K4.

2. Similar remarks hold for the Leonid

epochs, for the period 1930 to 1940, and much

material left out of K3 is included in K4.

3. As in the previous catalog rates obtained on Oct. 9 and 10, 1946 in the great

Draconid shower are omitted as being wholly

atypical.

4. Rates were omitted when they were

obtained by two or more observers and there

seemed no way of finding out what the rate for

a single observer was. The unit in the table is

the number of meteors seen by one observer in

one hour. Many thousands of otherwise good

observations were hence useless for K4.

5. Certain observers, including some of the

best of the Japanese, at times gave average

rates for periods of from 2 to 4 hours of continuous observing. Since there was no way of

determining what the rates were for each

separate hour, some thousands of these good

observations were necessarily omitted.

6. Occasionally an observer, not an AMS

member, has reported highly unusual rates,

quite contrary to what might be expected

under the prevailing circumstances and local

conditions. Such rates are open to suspicion

and have been omitted.

This is perhaps the place for a few general

171
172 SMITHSONIAN CONTRIBUTIONS TO ASTROPHYSICS

remarks about meteor observations. The more

reports are studied, the more apparent it becomes that rates such as those given in this

catalog can have meaning only when based

upon the work of many observers over a

period of several years. Even in the same

place and on the same night, observers standing

side by side may get different rates. Some

eyes are better than others; some observing

stations have clearer skies than others. Observations made in different directions, on the

same night and at the same place, may give

different rates—in fact, they usually do. This

realization was one of the chief reasons the

writer decided to compile this second catalog.

It should of course be used in connection with

K3, and the results for the same dates and same

hours compared. If they agree approximately,

we can be fairly sure that the rates given are

about correct. If they disagree badly, more

work for these dates should be carried out in

the future. Obviously, the rates that depend

upon large numbers of observations are more

reliable than those depending on few. In fact,

little confidence can be placed in rates that

depend upon the work of fewer than three

observers, unless confirmed approximately by

those in K3.

In the tabulation, an asterisk * indicates

that the rate given depends entirely on reports

from Australia. If a rate is enclosed in parentheses ( ), it is considered uncertain, either because the observer's percentage estimate (F)

was smaller than usual or the observer worked

somewhat less than a full hour. Such uncertain

values are given only when no others are

available. The rates usually show a decrease

for the last hour of a given night. There

are two obvious reasons: the approach of

morning twilight and the probable fatigue of

the observer.

The larger part of all the observations

consisted of meteors that were either plotted

or described. When plotting or describing a

given meteor, an observer will miss any meteors

appearing during the interval. Therefore, to

obtain the true hourly rate of meteors that could

have been observed during the period and in the

prevailing atmospheric conditions, a correction

was applied to the number of meteors reported.

The correction is given in the following formula:

no=

60 n

60—pn (1)

where n0 is the number of meteors that could

have been observed had the observer been

counting rather than plotting or describing

them; n is the number of meteors actually

observed; and p is the time taken to plot or

describe each meteor; pn in the formula is

expressed in minutes of time. The value of p

is an estimate based on the author's opinion

of the skill of the particular observer. In

applying the formula, the writer used tables

giving the appropriate corrections for the

various values of p; those values of p were

set as 20, 30, 40, and 60 seconds.

Another correction is usually necessary because the number of meteors observed during

a given hour depends to some extent on the

conditions for seeing, and whether visibility

was impaired by clouds, fog, moonlight, etc.

In the following formula,

Wo

(2)

rii represents the average number of meteors

that could have been counted by a skilled

observer during that period under ideal conditions. The number of meteors actually observed usually represents only a percentage of

the total observable under such conditions;

the factor F represents the observer's estimate

of this percentage. Under ideal conditions, F

was taken as 1.0; when F was 0.5 or less, the

observations were considered very uncertain and

were usually omitted. For the majority of

American reports used, the factor F was 0.7

or higher; there were comparatively few for

which F was 0.6 or 0.5.

For a few observations the author changed

the estimated F when the data themselves

obviously indicated that the original estimate

had been in error. In most cases, however,

the observer's estimate of F was used.

The correction for time lost (formula 1)

must always be applied before that for visibility

(formula 2). Otherwise the hourly rate will be

too high.

When the observer merely counted the

meteors, no correction was necessary for time
SECOND CATALOG OF HOURLY METEOR RATES 173

lost in plotting or describing, and therefore

formula 1 was not used, although the correction

for visibility conditions was still applied if the

value of the factor F was less than 1.0.

No system of correction can give perfect

results. Nevertheless, when one considers the

inherent difficulties in seeing and recording all

meteors that presumably appear in the observer's field of view, one may conclude that the

methods of correction given here yield a close

approximation to the true rates. However,

experience shows that when the rate is over

about 25 per hour, and the observer plots the

meteor paths, formula 1 becomes less and less

accurate. This is proved by certain instances

in which two persons worked side by side, one

plotting what he observed, the other counting

only. The latter nearly always obtained higher

rates. This source of error, however, is relevant for only a few nights in the year, and they

are dates for which we have so much data that

the final averages are little affected.

Professor Komaki corrects the Japanese

observations by using a factor F which presumably is the same as ours. It is noted, however,

that the values of F used by him seem to average

lower than in America. No attempt was made

here to further use formula 1 on the Japanese

observations since they were doubtless made

in a variety of ways by persons of widely different experience. This would seem to mean

that, if corrected by formula 1, the rates would

be somewhat higher in certain cases, but this

possible error is probably compensated for by

the lower value of F used.

It is safe to assume that the vast majority of

observers everywhere faced an area of the sky

centered at altitude about 50°, and somewhere

between northeast and southeast, as the AMS

instructions advise. Practically all observers

were in latitudes from 20° N to 50° N, the

majority between 25° N and 45° N. As to

longitudes, all the United States and Japan

and part of Canada were adequately covered.

The rates published in this table are of course

higher (on the average, 20 percent) than the

rates of meteors an observer will actually see,

unless he is counting under ideal atmospheric

conditions. In using this catalog, researchers

must keep this fact in mind. In general, the

figures given represent the number of meteors

that might have been counted by a skilled

observer at a good station on a moonless, clear

night when factor F was equal to 1.0. Under

conditions that fall short of this ideal in any

way, the number of meteors actually observed

will usually be smaller than the number given

in the table.

One sees a great disparity in the number of

reports for the various months, largely because

of the impossibility of inducing most American

observers to do much if any observing in the

period roughly from Dec. 15 to June 15. Of

course there are many honorable exceptions.

The Japanese did far better for this interval.

Acknowledgmen ts

Without the hard work and active cooperation

of many hundred observers, the data on which

the table is based would not have been available,

and the preparation of the catalog would have

been impossible. The names and number of

reports of the American observers are given in

our "Annual Reports"; the names and contributions of the Japanese observers are fully

given in the "Provisional Reports of Japanese

Meteor Committee," prepared by Professor

Kojiro Komaki. To all the persons whose

names appear in the publications just mentioned

and whose work could be used in K4, our most

grateful thanks are due.

The actual preparation of the catalog by the

author has been a continuous, and sometimes

major, occupation during the interval from

1958 to the present. In this he has had

practically no clerical help.

Finally, the greatest appreciation is due to

Professor Kojiro Komaki for his invaluable

aid in securing, preparing, and submitting the

Japanese work, and to Dr. Fred L. Whipple,

Director of the Smithsonian Astrophysical

Observatory, for publishing the completed

catalog.

References

[Meteor Notes]

1901-1950. Popular Astronomy, vols. 9-58.

1953-1956. Meteoritics, vol. 1.

OLIVIER, C. P.

1921. Parabolic orbits of meteor streams. Publ.

Leander McCormick Obs., Univ. Virginia,

vol. 2, parts 4 and 7.
174 SMITHSONIAN CONTRIBUTIONS TO ASTROPHYSICS VOL. 8

1935. Results derived from 8600 meteor observa- i 958 . interim reports nos. 28, 29, and 35. Radio

tions made during the years 1919-1925. »* • r> t> u J r> n ^.

_, T , ° ~ . _ TT . Meteor Res. Prog., Harvard Coll. Obs.

Publ. Leander McCormick Obs., Univ.

Virginia, vol. 5, part 1. 1959-1963. Annual reports for 1956-1963. Amer.

1950. Some results from data secured by the Ameri- Meteor. Soc, Flower and Cook Obs.,

can Meteor Society. Proc. Amer. Phil. Univ. Pennsylvania, Reprints nos. 115,

Soc, vol. 94, pp. 327-335. 119 ; 13 1 13 7 143) an d 14 6

1957. Long enduring meteor trains and fireball ««-« /-i A . » . i . A r, ...

*.. __ * . Tiui o i mi I960. Catalog of hourly meteor rates. Smithorbits. Proc. Amer. Phil. Soc, vol. 101,

 e J

pp 296-315 sonian Contr. Astrophys., vol. 4, pp. 1-14.
SECOND CATALOG OF HOURLY METEOR RATES 175

Month

and Day

January

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

6

b

M

8

(16)

1

7

20

17

o

2

1

1

2

1

1

7"

M

12

9

(22)

4

5

7

12

10

2

4

7

6

2

8

10

2

3

2

13

13

2

12

(40)

3

15

4

6

2

0

2

3

1

1

2

2

2

2

2

2

5

4

1

2

2

1

1

1

1

1

1

2

1

3

4

1

1

2

g

M

5

14

12

8

7

4

3

7

8

4

3

4

5

6

3

7

5

6

5

5

6

5

5

9

6

5

6

4

7

AVERAGE

>

o

l

2

3

4

1

2

2

5

2

2

1

1

3

5

2

3

3

2

5

1

2

4

6

7

6

3

5

4

6

o

M

11

7

14

17

5

5

5

4

4

14

10

4

0

6

6

10

4

9

4

2

1

3

5

7

7

5

12

6

i

o

2

5

6

2

1

4

1

2

2

2

2

1

1

1

2

2

3

2

6

2

1

2

7

3

1

3

2

6

HOURLY RATES

10

M

10

11

4

3

3

16

6

6

4

6

5

10

4

14

12

6

4

3

3

4

3

6

o

3

5

1

2

1

1

4

1

1

2

3

1

2

3

4

2

5

3

1

2

1

2

u

M

9

12

4

6

5

4

10

10

6

5

4

4

10

9

9

8

2

2

6

2

8

4

OF VISUAL

/xal Astronomical Time

O

5

9

1

4

1

3

1

2

2

2

1

1

1

6

1

2

2

2

1

1

2

2

12b

M

7

5

22

2

3

4

7

11

1

6

6

5

3

8

7

7

9

4

o

l

3

6

3

1

2

1

1

1

2

2

1

1

1

1

1

1

1

METEORS

13b

M

6

12

16

14

6

4

4

21

4

8

2

7

4

o

1

3

15

2

1

1

2

1

1

2

1

1

1

14

M

12

17

30

14

12

17

4

16

9

4

8

9

11

12

8

6

9

14

b

o

3

13

13

4

1

1

1

4

2

2

1

2

1

2

1

1

2

1

15b

M

10

20

35

18

10

9

6

10

8

10

9

4

3

10

4

O

4

11

24

10

1

1

2

1

2

1

1

1

1

2

1

16b

M

11

16

42

15

15

10

15

8

20

14

5

11

18

(3)

32

14

4

10

(12)

10

21

9

o

6

16

28

15

1

1

1

1

1

1

4

1

2

1

1

1

2

3

1

3

1

3

i7h

M

10

16

43

19

14

9

8

15

8

22

13

16

13

14

15

12

8

11

18

(4)

9

O

3

13

19

13

2

3

1

2

1

1

4

4

1

1

1

1

1

1

1

1

3

18b

M O

6 1

TOTAL FOR JANUARY: 9018

February

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

9 1

1 1

6

7

17

9

4

4

6

3

(18)

2

1

10

2

1

1

4

5

5

2

7

5

10

4

3

1

1

3

1

1

1

1

1

3

1

2

1

1

1

3

1

3

3

3

1

1

1

5

6

8

8

3

4

4

4

2

2

12

3

4

7

7

6

8

5

5

3

4

5

3

8

6

11

6

5

9

3

2

5

7

2

5

4

4

2

2

2

4

2

5

3

4

3

5

4

3

5

11

6

6

2

3

7

4

1

6

8

10

10

4

2

4

5

4

15

6

9

8

12

6

4

4

4

7

8

16

6

9

6

4

3

4

4

1

1

3

2

3

5

1

2

4

1

2

3

1

2

3

7

4

2

3

3

4

2

8

15

12

10

4

4

6

9

4

17

2

1

3

7

6

6

2

6

9

7

2

1

2

1

2

1

2

2

2

1

1

1

1

5

9

3

1

2

1

2

12

6

6

3

2

11

4

2

7

6

7

10

9

0

6

2

2

1

1

2

1

2

1

1

6

1

1

2

1

3

11

11

8

4

13

6

12

2

3

16

8

6

1

2

1

1

1

1

3

2

1

1

2

1

9

12

10

14

4

6

9

7

10

2

3

1

1

1

2

5

1

1

7

8

9

7

12

5

14

14

6

13

6

6

12

5

8

1

1

3

2

1

1

1

2

2

1

2

2

2

1

1

5

13

12

11

14

6

8

12

5

12

20

10

10

7

5

5

1

4

2

2

1

1

2

1

1

1

6

2

2

1

2

1

10

12

10

8

7

6

14

6

10

9

6

7

15

8

13

(3)

1

1

2

4

1

2

1

1

1

1

1

3

4

3

1

1

8

22

12

6

11

8

6

7

6

4

9

2

1

5

2

1

1

3

1

2

1

2

TOTAL FOR FEBRUARY: 2960

M=corrected average number of meteors observed. O=number of observations on which M is based. 6h=0601 to 0700; 7h=O7Ol to 0800, etc.
176 SMITHSONIAN CONTRIBUTIONS TO ASTROPHYSICS

AVERAGE HOURLY RATES OF VISUAL METEORS—Continued

Month

and Day

March

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

April

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

6

h

M O

7

h

M

12

3

3

5

5

10

4

3

4

4

1

2

3

1

7

17

6

2

4

4

5

(10)

7

4

3

1

2

1

3

4

5

3

O

1

1

1

1

1

2

1

1

2

1

1

1

1

2

1

2

1

1

2

2

1

1

2

2

1

1

1

1

1

2

1

1

8"-

M

6

3

4

6

3

5

8

3

3

15

2

6

5

3

7

3

1

4

3

13

6

4

4

5

7

3

6

3

5

1

16

9

4

2

5

2

4

1

6

5

8

4

11

2

3

3

6

5

6

8

6

7

4

8

2

5

2

9

o

4

5

5

1

3

2

3

1

3

2

1

5

3

5

7

3

2

5

3

3

6

5

6

3

8

3

3

2

6

3

2

1

2

1

4

2

1

3

2

3

9

5

2

2

3

6

4

7

5

6

6

2

7

5

2

5

2

1

9"

M

6

5

4

6

3

7

9

4

8

4

10

2

5

4

3

10

4

5

4

4

5

6

10

4

3

20

5

4

6

2

10

13

2

4

6

7

8

8

3

29

5

6

6

5

6

10

7

4

5

6

4

O

5

1

1

1

1

3

1

1

5

3

3

1

2

5

1

8

2

7

4

1

5

1

4

2

1

2

2

4

3

2

2

1

1

2

7

2

4

1

5

1

9

2

6

1

2

2

8

4

6

1

4

IO»>

M

9

9

3

3

10

10

7

6

26

4

3

5

18

4

6

4

3

8

4

4

5

7

6

6

5

12

5

5

13

11

2

1

9

9

5

6

3

8

6

1

6

12

9

4

10

22

26

6

7

4

6

O

1

3

3

1

2

1

1

2

1

1

2

5

1

1

2

1

1

3

5

2

1

1

3

3

3

4

2

3

2

1

2

1

3

3

2

7

2

5

3

3

2

2

12

8

9

1

1

2

3

4

5

l

M

2

3

4

7

8

4

9

5

5

5

7

5

8

10

5

5

8

11

4

4

9

13

7

4

4

8

9

2

10

0

4

10

6

4

4

5

8

4

4

8

6

10

21

17

10

5

5

10

7

Local Astronomical Time

h

O

1

1

1

2

3

1

3

1

2

3

1

5

2

1

1

5

5

1

2

1

3

1

2

2

1

1

3

4

1

1

1

2

5

3

4

3

4

3

2

19

8

8

1

1

2

3

3

2

1

12k

M

8

11

11

13

9

12

2

6

(14)

3

3

7

3

9

5

10

11

10

4

5

5

6

6

9

3

6

5

7

5

8

10

7

9

6

15

10

7

19

15

14

11

9

12

o

2

1

2

2

1

2

1

1

1

1

1

1

1

1

4

8

1

2

1

1

3

1

1

2

2

1

1

2

2

2

2

7

1

6

24

15

4

1

5

4

1

3

1

13

M

19

8

9

12

9

5

7

4

5

4

5

8

6

3

4

5

6

6

6

12

8

(4)

16

3

2

8

9

12

11

22

4

11

7

11

4

4

h

o

2

2

1

2

1

2

1

1

2

1

5

5

1

1

2

3

2

2

1

1

1

1

1

1

2

8

17

22

4

1

1

6

2

1

2

1

l

M

10

20

14

14

4

5

12

8

6

15

4

8

4

5

9

9

10

5

8

7

4

6

5

10

6

4

6

5

9

6

9

12

14

14

8

12

5

10

7

\h

o

2

2

1

1

1

3

2

2

1

1

1

1

3

3

1

3

1

2

1

4

2

2

1

1

1

1

1

1

4

7

15

15

4

2

4

2

2

1

1

15

M

8

4

5

6

10

5

4

6

8

6

8

10

6

11

8

9

6

6

6

11

9

8

12

8

6

(3)

9

8

11

10

4

O

2

2

2

4

1

1

2

2

1

3

4

3

1

3

2

3

1

1

2

4

6

14

16

2

2

1

3

2

3

2

1

16

M

6

6

7

8

10

8

5

9

8

11

8

8

6

11

5

8

4

6

7

ii

o

3

1

1

2

1

3

1

3

2

1

2

1

1

1

1

5

1

3

1

17"

M

8

6

7

3

o

2

1

1

1

igh

M O

TOTAL FOR MARCH: 3141

9

12

27

(20)

(18)

6

9

2

8

3

5

2

2

1

1

1

2

1

1

1

1

1

TOTAI

16

. FOR

1

APRIL: 5363

M-corrccted average number of meteors observed. O=number of observations on which M is based. 6h=060l to 0700; 7>>=O7Ol to 0800, etc.
SECOND CATALOG OF HOURLY METEOR RATES 177

Month

and Day

May

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

6"

M O

7"

M

3

0

1

1

AVERAGE

o

l

l

l

3

8"

M

2

2

5

4

3

0

6

6

2

4

6

7

6

6

11

4

8

7

4

5

6

8

6

4

4

o

1

l

2

2

1

1

2

2

1

2

2

1

2

2

4

4

5

1

2

4

2

2

1

3

5

M

6

5

12

9

8

4

9

5

4

2

3

5

1

16

9

12

2

13

3

4

6

4

5

6

2

4

6

4

4

HOURLY

9"

O

2

7

2

4

5

2

1

1

2

2

3

3

1

2

6

2

2

3

1

11

5

5

13

3

1

7

6

12

14

10

M

5

3

9

2

14

7

5

4

2

9

11

7

6

11

6

11

14

4

6

4

5

6

5

4

7

5

3

RATES

h

o

2

1

1

1

5

6

2

2

2

1

1

2

1

4

5

6

3

2

6

3

5

7

6

1

7

3

17

I

M

13

6

5

13

7

3

2

9

6

6

3

7

16

4

11

7

8

6

7

6

14

9

8

6

OF VISUAL METEORS—Continued

Local Astronomical Time

O

1

2

3

4

1

1

1

2

3

2

1

2

3

3

6

1

2

5

5

3

3

4

2

5

12

M

9

0

6

12

15

3

5

3

6

5

6

8

14

3

5

3

2

7

14

6

8

10

4

h

o

2

1

3

2

1

1

1

1

2

1

1

2

3

1

2

1

1

4

1

1

4

1

5

M

2

3

12

6

3

3

5

4

23

6

0

9

6

6

9

8

24

13k

O

1

1

6

3

1

1

1

1

2

2

1

3

4

1

1

2

1

l

M

7

10

12

17

9

8

10

9

13

8

12

5

17

8

8

7

3

4

3

3

4

11

7

17

o

2

10

6

10

10

4

3

2

3

2

1

1

1

1

2

1

1

4

1

1

1

1

4

5

M

12

13

29

18

12

12

12

16

9

9

9

9

12

9

8

8

2

10

0

7

6

15

0

(27)

h

o

5

11

6

12

14

6

6

1

4

6

3

4

3

1

1

1

2

1

1

4

1

1

1

1

M

14

15

22

17

13

I6h

O

1

1

2

6

5

I7h

M O

17 1

17 l

21 1

18*

M O

TOTAL FOR MAY: 5084

June

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

3 1

7 3

4 2

7 3

5 6

15 1

6 3

(15) 1

7 2

3 1

5 3

6 1

6 1

3 1

2 1

4 4

4 2

4 2

3 1

5 1

4

6

20

4

5

6 5

11 6

9 4

4 4

8 8

8 12

9 9

5 9

7 8

6 9

5 5

2 2

7 5

7 3

6 2

9 2

21 1

4 2

10 1

16 1

(8) 1

TOTAL POR. JUNE: 5561

M=corrected average number of meteors observed. O=number of observations on which M is based. 6h=0601 to 0700; 7h =070l to 0800, etc.
178

SMITHSONIAN CONTRIBUTIONS TO ASTROPHYSICS

Month

and Day

July

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

6b

M O

7

h

M

4

1

2•ft 1

AVERAGE HOURLY

o

1

1

1

1

1

g

M

3

3

3•ft 4

14

4

7

14

2

4

5

4

10

9

11•ft •ft 6•ft 7

11

3

6

6•ft

O

1

1

1

1

1

2

2

1

2

2

3

1

3

2

2

1

4

3

2

7

3

2

3

6

6

7

M

12

12

7

10

12•ft 5

7

6

6

6

12

9

7

4

5

9

7•ft 10

7

8

7

12

6

9

8

14

9

7

10

o

3

7•f 5

t «-i 4

6

9

1

4

6

9

11

10

2

10

7

6

3

10

6

11

4

11

11

13

14

15

18

19

7

10

M

6

13

11

10

13

7

9

8

3

7

4

13

6

8

6

8

7

9

8

11

11

7ift 9

8

11

13

11

10

11

9

RATES

b

o

4

3•f7

t •f 6

t •ft 6

1

4

3

8

13

11

8

8

11

8

10

15•ft

11

8

9

19

18

14

18

18

17

4

l

M

6

3

8

8

14

11

10

9

2

4

8

21

11

9

8

9

8

8

8

8

12

10

11

12

7

10

13

13•ft

18

8

OF 'VISUAL METEORS—Continued

Local Astronomical Time

l

h

O

3

2

2

4

4

3

9

6

2

4•ft 2

8

10

8

6

10

8

8

18

10•ft 12

7

11

23

21

28

26

21

3

l

M

10

6

14

7

14

11

13

12

8

7

6

10

10

10

11

12

7

8

11

14

12

10

9

12

15

14

14

20

19

17

b

O

3

4

3

3

3•ft 11

6

6

6•ft 7

6

2

11

10

4

9

15

7

6

6

7

9

18

23

34

27

31

13

l

M

9•ft

13

7

16

6

7

20

10

13

7

1•f 7

t •ft

10

10

12

11

11

12

12

11

7

15

15

15

25

18

21

20

23

O

3

2

1

3

1

2

3

2•ft 3

2

3

3

3

2

8

6

6

6

11

9

6

6

5

5

14

22

30

23

39

14

l

M

25

7•ft 8

18

16

4

4

12

12

11

8

14

9

9

9

14

11

17

18

10

7

19

19

17

15

18

16

20

19

20

h

o

1

3

2

3

1

2

2

1

6

1

1

1

3

3

1

1

6•ft 2

9

2

3

1

3

3

14

16

21

20

24

10

15b

M

0•f7t 22

6

10

9

8

6

11

7

7

9

21

5

14

12

11

14

11

10

15

21

21

17

20

20

o

1

1

1

2

1

1

1

2

1

1

1

4

1

1

2

3

1

1

3

2

6•ft 14

12

9

15

6

16b

M

0

9

8

11

20

20

13

13

32

o

1

2

1

1

1

2

3

2

1

I7h

M O

12 1

18b

M O

TOTAL FOR JULY: 20833

August

1

2

3

4•ft 6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

4 1

9 1

7

9

9

6

2

10

11

12

13

12

12

17

13

14

26

9

8

4

8•ft 6

8

6

6

9

12

7

8•ft 7

6

4

3

1

2

1•f 8

t 6

6

19

30

13

15

10

7

1

3

6•ft 4•ft 2

4

2

7

11

3

2

2

1

2

9

9

9

9

10

8

14

12

12

12

18

19

16

14

14

10

10

6

12

7

8

7

11

9

8

10

8

6

8

9

6

7

13

10

10

7

11

11

11

12

53

79

36

41

26

15

9

12

7

9

8

6

4

4

11

11

7

8

4

6

8

7

10

14

9

10

11

11

13

13

13

14

22

21

18

15

15

9

17

10

9

15

16

9

11

12

8

8

10

6

6

5

6

5

11

13

16

10

12

12

7

20

69

102

55

33

26

21

13

13

11

9

7

8

10•ft

13

10

10

4

6

6

7

4

17

11

13

10

11

12

15

11

17

16

25

24

18

15

9

11

14

13

16

7

11

12

14

12

9

12

16

10

8

6

8

8

9

9

14

8

8

7

8

12

48

122

60

35

25

11

10

16

9

4

2

1•ft 2

6

3

9

2

4

4

8

3

18

11

11

11

10

10

13

14

18

18

30

30

20

19

15

14

22

11

16

13

10

6

13

21

16

12

12

11

8•ft

20

9•ft •ft

11

8

8

11

18

19

63

129

76

39

25

11

7

9

8

3

2

2

1

2•ft 4

7

4

4

4

4

1

18

14

10

13

14

14

15

13

18

22

34

32

21

20

16

17

22

13

20

12

14

14

21

15

16

9

11

15

8

9

13

3

9

12

9

12

21

25

59

120

69

38

23

11

8

11

6

2

1

1

1

4

3

6

4

3

4

3

18

11

18

13

12

15

17

10

19

23

37

34

24

24

17

15

10

14

17

14

10

12

17

14

15

10

18

17

14

10

9

9

3

3

10

8

15

16

20

54

114

68

29

20

8

8

1

2

1

2

4

1

3

3

4

4

2

3

2

4

15

15

19

23

14

22

18

12

17

25

38

40

22

22

17

16

9

8

4

18

10

19

12

13

14

10

15

22

14

9•ft •ft 4•f 8

t

11

10

15

41

68

35

11

10

6

4

1

2

1

2

3

1

1

1

4

3ift 2•ft

15

24

18

15

47

15

10

13

19

35

44

20

22

3

26

12

10

13

10

11

15

14

2

1

1

4

1

3

2

4

9

11

8

4

1

1

1

1

1

1

1

1

1

2

16

20

4*

13

1

1

1

2

TOTAL FOR AUGUST: 67082

M -corrected average number of meteors observed. O=number of observations on which M is based. 6>- =0601 to 0700; 7h =0701 to 0800, etc.
SECOND CATALOG OF HOURLY METEOR RATES 179

AVERAGE HOURLY RATES OF VISUAL METEORS—Continued

Month

and Day

September

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

October

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

6

h

M O

7"

M

4

6

14

4

7

2

7

6

10

3

6

6

6

6

4 1

9 2

24 1

7 1

14

9

10

7

6

5

5

4

25

6

6

6

11

9

10

10

14

6

5

17

10

6

o

1

l

3

1

4

2

2

3

3

3

2

2

2

3

2

4

2

8

9

9

4

4

1

3

3

4

4

1

3

2

5

1

4

1

1

2

8*

M

6

4

5

8

5

1

19

6

18

12

3

10

£

13

12

7

4

7

7

6

3

6

6

5

5

7

4

2

16

4

3

2

10

7

7

5

9

9

10

4

9

6

10

8

9

11

15

6

9

13

9

7

7

12

10

8

6

6

o

2

1

3

2

9

1

3

1

2

2

2

2

1

4

4

1

7

8

11

3

3

3

4

5

7

1

3

2

2

2

2

1

3

8

9

9

14

6

11

2

4

6

2

13

9

8

12

3

4

3

10

3

3

4

2

2

3

2

9 h

M

14

7

8

7

8

8

12

10

7

12

5

5

8

9

5

27

9

11

2

6

6

6

9

8

5

10

10

11

11

6

6

4

10

7

6

12

5

12

7

8

8

13

8

10

8

10

8

6

11

6

9

9

6

8

14

9

12

o

4

7

10

2

6

5

5

5

5

5

5

2

7

3

1

1

7

6

4

5

9

4

1

4

4

3

3

4

1

1

2

2

1

2

5

8

6

9

9

11

3

3

5

5

5

3

2

2

3

6

1

5

4

1

2

4

3

1C

M

10

12

12

11

9

10

10

15

5

8

4

18

13

12

21

21

7

10

4

8

8

8

10

8

6

7

10

7

8

3

9

7

6

14

8

6

7

10

8

11

10

4

4

12

16

10

14

8

15

5

14

10

12

12

14

b

o

2

2

7

3

6

5

4

3

4

3

2

2

3

3

2

1

3

3

2

3

2

2

2

3

2

3

3

2

1

1

1

3

2

6

5

8

9

10

2

1

1

1

2

6

3

3

4

4

5

1

5

4

2

4

2

M

14

(2)

3

9

17

7

8

9

6

8

16

12

11

12

4

8

10

4

9

6

10

6

10

4

8

5

1

14

12

12

5

13

9

7

12

6

12

12

8

12

15

14

10

14

22

14

9

14

12

4

9

14

Local Astronomical Time

h

O

2

1

1

2

5

3

2

1

5

3

1

1

2

2

3

4

3

2

2

2

1

2

3

2

1

1

1

2

3

1

3

3

6

7

10

3

2

3

2

3

2

4

7

7

6

4

4

3

2

2

2

1

12

M

4

8

1

11

12

(9)

10

10

11

12

8

18

13

8

9

16

16

8

11

4

10

10

10

10

10

4

16

9

6

12

12

13

13

17

11

10

19

20

16

16

13

17

17

8

13

14

20

b

O

2

1

2

3

1

1

1

2

1

2

1

2

3

3

1

2

3

2

3

1

4

1

2

3

1

2

5

4

4

6

2

5

6

3

3

7

10

16

11

10

5

8

7

1

4

1

1

13b

M

10

15

5

14

16

8

12

8

14

21

24

16

22

15

10

8

15

10

10

6

4

6

13

11

18

5

-11

16

12

16

10

18

8

14

15

25

20

19

15

17

17

4

11

20

10

o

2

1

3

4

1

1

1

2

2

1

1

2

2

2

1

2

2

6

1

1

1

1

2

4

2

3

4

2

4

3

3

3

4

8

12

16

21

15

6

12

6

1

3

4

1

14"

M

10

8

10

10

6

8

10

3

6

15

14

8

10

9

15

12

4

11

12

13

12

11

5

6

17

16

17

6

12

13

11

9

14

26

21

12

12

21

21

19

22

18

16

23

19

21

16

12

O

4

2

2

2

4

1

4

1

2

1

2

1

2

1

2

3

1

2

1

6

4

3

1

1

3

2

2

2

5

3

4

4

2

1

1

4

4

9

10

19

14

7

8

3

1

1

2

4

15"

M

8

(5)

7

4

8

10

8

18

10

8

6

13

8

3

15

12

16

13

13

11

10

3

9

14

16

10

9

14

9

22

11

18

16

24

26

25

20

22

17

14

12

13

13

17

14

10

o

2

1

2

2

1

2

1

2

4

2

2

1

2

1

2

1

2

3

5

3

K

M

(6)

2

14

14

6

7

16

3

18

15

20

8

11

10

11

o

1

1

1

1

1

1

1

1

2

1

2

1

1

2

2

17'

M

(4)

(6)

O

1

1

M O

TOTAL FOR SEPTEMBER: 5329

1

2

1

3

5

1

2

3

1

1

2

5

7

12

8

11

13

11

7

4

1

1

3

1

3

2

9

17

10

11

18

12

10

10

16

5

12

16

25

17

18

44

24

24

23

17

14

8

13

12

17

13

12

1

1

1

1

1

4

2

1

1

1

2

1

2

7

13

3

12

9

5

5

6

2

2

5

2

1

3

TOTAL FOR

11

3

22

22

18

6

2

1

1

3

1

1

OCTOBER: 15214

M^corrected average number of meteors observed. O-=number of obvcrsationa on which M ia baaed. 6h=0601 to 0700; 7h=0701 to 0600, etc.
180 SMITHSONIAN CONTRIBUTIONS TO ASTROPHYSICS

Month

and Day

November

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

M

7

4

11

5

2

2

2

3

4

1

O

1

1

1

1

1

1

1

1

1

7

h

M

6

9

5

8

3

5

4

6

9

7

5

8

14

7

8

4

4

7

1

10

25

4

8

4

6

6

AVERAGE HOURLY

0

2

1

2

4

2

4

1

2

3

1

1

2

2

1

2

1

5

2

1

1

3

1

3

1

3

2

g

M

9

12

8

8

3

6

5

6

13

4

10

5

2

8

8

8

6

4

8

6

18

4

4

6

6

9

1

o

3

2

5

9

1

4

2

2

5

2

3

4

2

4

3

8

5

2

5

7

3

2

2

4

6

5

9

M

6

6

8

11

5

14

4

13

4

6

10

6

7

3

11

8

7

9

5

7

8

8

5

10

7

6

12

6

i

o

2

2

1

6

1

3

3

3

3

4

2

2

4

1

11

2

5

5

5

1

2

5

6

1

3

3

2

5

10

M

11

14

8

12

10

14

7

3

6

7

6

10

10

8

14

4

11

2

4

11

17

16

6

8

9

4

RATES OF '

o

2

2

2

3

5

1

9

1

2

3

3

2

7

1

12

4

3

3

1

3

1

3

1

2

5

1

M

10

17

7

14

11

11

8

6

18

14

7

12

13

11

10

13

2

7

4

7

8

7

10

7

4

10

11

12

VISUAL METEORS—Continued

Local Astronomical Time

Ilk

O

2

3

1

2

7

3

8

1

6

5

3

1

1

7

5

15

2

2

1

1

1

3

1

1

1

2

3

1

I;

M

20

9

18

6

4

11

10

16

8

15

18

8

9

10

15

7

2

3

6

7

ll

8

9

12

4

10

10

8

o

2

1

5

5

1

8

1

8

4

2

1

2

10

12

19

2

2

1

1

1

3

4

4

1

1

2

2

2

12

M

20

6

13

13

6

6

17

5

16

2

12

12

2

14

16

18

8

19

9

6

10

9

11

19

11

14

h

o

1

2

1

4

6

2

5

1

2

2

2

2

1

11

17

31

8

1

4

1

2

5

4

1

1

1

u

M

17

7

16

5

17

3

18

6

15

6

14

17

23

25

13

8

9

13

12

15

10

8

6

14

h

o

1

1

2

7

5

1

2

3

6

2

2

12

24

32

9

2

4

3

3

3

5

2

1

2

15k

M

10

4

12

16

14

14

12

8

17

8

12

15

27

34

13

11

17

14

14

14

15

11

19

6

22

7

ll

6

O

1

2

2

1

4

2

6

2

10

4

6

18

23

33

13

4

3

8

2

1

3

4

3

3

2

1

2

1

K

M

8

10

15

16

11

12

6

12

15

18

16

22

33

IK

22

28

16

13

27

9

12

16

15

21

12

14

O

2

3

1

6

6

6

3

10

5

2

6

18

25

11

5

2

9

7

1

3

5

3

9

3

2

2

V)

M

8

4

9

15

20

18

20

31

29

22

12

9

8

19

12

12

11

h

O

1

1

1

1

1

4

3

16

7

2

4

1

1

3

3

1

1

18*

M O

15 2

5 1

December

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

1 JC 16

17

18

19

20

OO

22

23

24

25

ox26

O*7 2y

28

29

30

31

7

16

6

21

3

1

2

1

1

1

3

4

8

3

6

5

5

4

20

2

3

3

4

5

3

6

3

7

5

4

3

3

3

2

1

2

2

2

1

4

1

1

1

3

4

3

2

1

3

3

2

2

6

5

4

7

9

4

7

6

13

5

13

17

26

66

9

6

6

12

9

4

5

12

8

5

4

5

4

4

4

7

4

2

6

4

1

6

3

4

3

5

3

5

4

8

9

4

2

1

2

4

4

4

2

2

1

4

3

1

3

2

5

2

15

6

6

16

5*

8

5

7

7

5

10

15

33

58

8

10

12

8

4

4

6

19

13

9

6

4

4

6

3

2

6

1

6

2

3

4

2

3

4

4

5

7

7

30

13

6

3

3

4

1

3

6

1

3

1

4

1

4

6

1

1

2

23

8

12*

7

4

6

11

7

14

19

36

18

4

10

14

14

7

10

11

4

4

8

7

1

3

10

5

6

1

3

4

3

3

7

7

14

30

9

3

2

1

1

1

1

4

2

2

4

1

1

1

2

21

18

18

11

5

12

13

10

14

13

20

24

45

20

6

14

7

11

5

3

6

1

5

1

3

1

1

2

3

3

5

6

10

16

26

22

2

3

4

2

1

1

2

4

14

6*

15

11

10

10

21

13

11

21

36

48

30

17

20

8

4

10

7

1

1

1

8

2

1

2

3

2

2

3

4

2

9

22

30

18

5

1

3

1

1

1

1

1

1

1

16

13

12

14

8

16

21

38

55

28

16

12

16

13

12

13

3

6

1

2

8

9

2

1

1

2

4

3

10

17

25

10

3

2

1

6

3

1

1

1

1

1

1

1

10

20

14

5

13

8

18

18

35

49

32

13

21

16

10

11

4

10

3

11

3

1

2

1

1

2

3

6

8

20

5

3

2

2

4

3

2

1

1

1

12

18

16

14

19

15

11

22

20

32

60

44

22OO CO

17

12

14

5

9

n

9

10

TOTAL FOR

2

1

4

2

3

3

1

4

4

5

12

5

2

1

1

1

5

2

3

1

1

1

2

14

10

15

15

17

16

14

20

21

22

57

32

20

2

14

24

14

13

8

8

14

14

8

10

18

2

2

1

3

7

3

2

6

9

5

15

3

4

1

1

1

1

5

2

2

2

1

1

2

7

SJOVEMBER: 15993

17

20

17

24

8

14

19

16

16

22

54

19

22

16

8

9

12

14

11

8

13

9

8

11

1

1

2

2

2

3

2

4

3

11

4

1

4

1

2

1

2

3

1

3

1

1

2

2

14 1

TOTAL FOR DECEMBER: 22351

GRAND TOTAL: 177931

'corrected average number of meteor, obaerved. O-numbe r of ob«rvatio M on which M i. ba«d. 6>-060 1 to 0700; 7>-<W>l to 0800, etc.

U.S. GOVERNMENT PRINTING OFFICE : 1965 O—746-363