247 4432 248

messen wird, und dieser Winkel nimmt offenbar mit wachsen- dem d zu. Wir sehen also, daO

11. d u r c h d i e W i r k u n g d e r b r e c h e n d e n G a s h u l l e e i n Pu i ik t d e r S o n n e n o b e r f l a c h e um so l a n g e r s ich t - b a r b l e i b t , je groOer s e i n A b s t a n d vom A q u a t o r d e r S o n n e ist .

Diese Erscheinung hat dazu gefiihrt, daO sich die Um- drehungszeit der Sonne um so groi3er ergab, je groDer die heliographische Breite der Flecke war, aus deren Sichtbarkeits- dauer sie bestinimt wurde. Auch beim Jupiter ist dieselbe Erscheinung beobachtet worden, und sie wiirde sich ohne Zweifel auch bei der Erde zeigen, wenn wir sie von einem anderen Weltkorper aus beobachten konnten.

Uberschreitet die Breite 6 eine gewisse Grenze, so schneidet der Fleck auf seinem Wege die Sichtbarkeitsgrenze nicht mehr, bleibt also inliner sichtbar und beschreibt schein- bar eine ellipsenartige Kurve. Leider treten in hoheren helio- zentrischen Breiten Flecke bekanntlich nicht auf.

Darmstadt, I 9 I o Mai.

Ich bin daran erinnert worden, daO ja die Geschwindig- keit eines Fleckes am Rande der Sonnenscheibe direkt inii Hilfe des Dopplerschen Prinzipes bestinimt wurde, glaube aber nicht, daO dadurch der Kern der obigen Ausfuhrung beruhrt wird. Was man mit Hilfe des Dopplerschen Prinzips bestimmt, ist nicht die in die Gesichtslinie fallende Kompo- nente der Geschwindigkeit eines Punktes der Sonnenober- flache selbst, sondern des virtuellen Bildes dieses Punktes, das man erhalt, wenn man die gebrochenen Strahlen eines Elementarbiindels bis zuin Schnitte ruckwarts verlangert. Durch den Astigmatismus dieses Bundels wird die Genauig- keit dieser Messungen weiter beeintrachtigt. - Jedenfalls scheint mir eine Erklarung, die die beohachtete Erscheinung als notwendige Folge der Strahlenbrechung in der schon durch die Spektralanalyse als vorhanden nachgewiesenen Atniosphare der Sonne darstellt, einer Erkliirung durch schwer vorstellbare, ganz unveranderliche Stromungen auf der Sonnen- oberflache vorzuziehen zu sein.

Ferd. Meisel.

Declinations and Proper Motions of fifty -five Stars. By Kiyofusa Sotome.

The following is a summary of results relative to the declinations of those stars which I have taken in my program of the latitude-variation work in Tokio since 1907. As the library of the Tokio Astronomical Observatory recently has gained possession of nearly all of the principal star-catalogues ever published, I was enabled to make investigations of those catalogues thoroughly, and to extract the star-positions directly from the original copies. The standard system I adopted for the present purpose is Auwers' New System of the Fun- damental Catalogue of the Berliner Jahrbuch. So I might have simply used his Tafeln zur Reduction von Stern - Catalogen auf das System des Fundamentalcatalogs des Berl. Jahrbuchs, (A. N., Erg.-H. 7), to convert several catalogue-positions directly to the said-system, were it not for the fact that there is a difficulty connected with his method of treatment of older star-catalogues, especially that of Piazzi, as was first detected by Prof. Battermann and subsequently announced by Prof. Auwers in A. N. 4200. This led me to prefer an indirect process which is materially the same as that taken by Dr. K. Hirayania in his deduction of declinations and Proper motions of 246 Stars<. *) So I first converted the original star-places to the A.G. System, applying the syste- matic corrections given A. N. 3195-6, 3413-4, and 34.63. The year 1900 was selected as the epoch of reference, and Struve's value of the precessional motion was used to bring the star-places to the chosen epoch; the correction due to the secular variation and the third term being applied as in the usual manner. These computations were greatly facilitated through the use of the tables giren in ))Annalen der Kais. Universitats - Sternwarte in StraOburg, Bd. II((. The correction

due to the variation of proper motion was also applied as far as known.

The weights were taken from the tables in A. N. 361 5 -16 and 3887-88, as far as possible, and in other cases, values considered suitable were assigned. From these positions for the epoch 1900, I computed the most probable values of declinations and proper motions referred to the A. G. system by the usual method of least squares. To the results thus obtained I applied the corrections given by Auwers so as to convert thepi to the new fundamental system of B. J. (correction table A. N. 3927 -29) according to the following formulae :

Qrgoo (B. J.) = drgoo (A.G.) + A d e l 8 7 5 + 1/4-AL + LdJ.1875 + '/rA"d

pd (B. J.) = pd (A. G.) + ' / loo [/%I,, + // 'd~] where L/d(,I~75 = Reduction of d of A.G; system to B.J. system

depending on right ascension d d d 1 8 7 5 = dito depending on declination A2Q, = Variation of r/S,,875 in IOO years A'dd = Variation of /&,875 in roo years Pd' = Annual proper motion in declination.

A complete description of the reductions will be re- served for a future opportunity, but for the present I simply set forth the resulting declinations and proper motions (re- ferred to Struve's value of the precession), together with some values of the latter given by several authorities for sake of comparison.

") Annales de I'Observatoire Astronomique de Tokyo. Tome IV. ~ e r F a x .

249 4432

Star

W.4g 19 La1 323 97 Piscium Fed 2 7 1

58 Androin. d 8 Trianguli La1 4381 13 Trianguli 33 Arietis La1 5 2 3 1

2' 61 Arietis La1 6469 La1 6820 La1 708 I 33 Tauri .x2 5 7 Orionis 3 5 Camelop. La1 11839 45 Aurigae La1 12560 La1 12803 La1 18278 18 Leonis min La1 19604 23 Leonis min Br I433 La1 23074 73 Ursae maj. D'Ag 3142 15 Can. ven. I I H. Can. ven La1 24803 La1 25441 La1 25653

Fed 5 2 7

D'Ag 3493 Fed 2594 La1 27927 La1 31192 La1 3 1438 La1 31694 La1 31970 Br 2 2 2 8

La1 32834 La1 36513 8 Cygni La1 37783 La1 38156 D'Ag 61 58

60 Pegasi 14 Androm. D'Ag 6351 La1 47ro4 La1 47216

La1 45034

Tokio

- Grot3

__ __

6m3: 6.42 6.25 6.46 4.95 5 . I C

6.75 6.26 5.7= 6.66 5 . 0 4 5 . 5 8 6.18 5.67 5.93 6.32 6 . 3 ~ 6.63 4.06 5.57 5 . 5 6 6 . 9 ~ 7 . 0 1

6.68 6.96 5.73 5.96 6.70 5.84 6.82 6.54 5.16 7.0'

5.59 6.5.2 6.54 6.52 5.76 6.79 6.77 5 . 5 7 5.90 6.52 6.54 6.35

6.77

6.59

4.88

6.90

6.66

5.26 5.60 5.98 5.76

5.40

a 1900

oh 9"55 0 14 2 t

I 24 25

I 33 5 ' 2 2 27

2 1 0 57 2 I 7 47 2 2 2 5 6 2 34 5c 2 45 I 7

3 9 3 3 1 5 2 7 3 26 18 3 38 3 3 46 2 4

3 5 1 8 5 49 I

5 56 33 6 8 38 6 ' 3 39 6 29 4c 6 36 1 4 9 11 42 9 5 0 4c 9 5 7 5 5 0 1 0 34 o 16 13 2 14 16 2 2 2 5 0

2 5 5 39 3 5 4 3 9 11

3 1 7 35 3 42 41 3 5 1 44 4 3 41 5 5 9 5 1 3 5 5 7 2 2

7 I 1 59 7 18 2 7

7 2 7 8 7 36 59 7 49 ' 5 9 16 8 9 2 8 3 9 45 2

9 53 54 40 55

2 56 3 3 6 58 3 26 2 2

3 3' 33 3 56 2 7

3 59 52

6 1900

+30° 58'4712: +40 10 28.9s + I 7 50 19.36 + 5 3 2 1 39.1S +37 2 3 5.5c f 3 3 46 o.oc +41 38 5I.9C "29 28 55.24 +26 37 53.54 f 4 4 28 53.72 + s o 34 0.48

+35 7 18.36 f 2 0 47 11.94

+36 8 40.10 +48 2 1 7 . 2 7

+ 2 2 5 3 6.83 + I Y 43 48.90 + 5 ' 34 33.16 + I 7 56 4.69 f 5 3 29 51.56

+32 39 16.45 i - 2 7 50 2 5 . 7 2

f 3 2 51 29.65 t 3 8 30 25.86 f 2 9 48 31.83

+38 31 34.73

f 4 I 44 13.74 + I 5 5 56.38

f 3 9 3 5 9 3 1 f 4 0 40 56.34 f 3 0 48 57.67 f 3 9 2 33.65

+56 1 5 58.78 t g z 19 6.78

+32 31 14.11 f 2 4 47 22.90 + s o 26 14.43 t z o 56 17 .75 t 4 3 56 52.16 t 2 7 14 51.26 t 4 0 4 21.63 t 3 1 '3 57 .27 t 2 4 33 45.48

+34 I 4 24.50 t 3 3 1 1 12.57 t 3 8 I I 19.71 t 2 9 5 5 35.13 t 4 4 50 1 7 . 2 0

t 2 6 18 2 5 . 5 5 t 3 8 41 13.85 i - 3 2 2 1 2.88 t 4 4 7 9.22 t z 7 7 6.21

t 4 6 40 10.05 t 3 7 8 59.32

~ ~~~

Annual proper rno

in Decl.

-0101:

--.or? t O . 0 0 ~

- 0.042

fo.02 1

+o.o66 - 0 . 0 4 ~ -0,027

- 0.0 I 5

~ _ _

-0.01 1

- 0.244

-0.034 - 0.00 I

- 0 ~ 0 ~ 4 - 0.03 I

- 0.009 - 0.042 - 0.035 - 0.09 I -0.019

-0.01 I

- 0.00 I - 0.00 I +0.008

-0.1 16 -0.024 -0.139 +0.004 - 0.0 I I

-0.010

f O . 0 0 I

+0.009 - 0.040 - 0.030 + 0 . 0 5 2

-0.01 I - 0.0'28 - 0.023 -0.013

- 0.07 2

fo .002

t o . 0 5 6 -0.124 -0.216

- 0.014 t o . 0 0 3 -0.352 - 0.003

- 0.048 - 0 . 0 2 7

-0.023 f O . 0 2 I

-0.1 11

'- 0.00 I

- 0 . 1 2 1

- z w

~ - 1.8( 2.8: 5.1( 2.95 9.2r

I7.9j 0.7! 4.5:

11.5:

4.5: 11..3:

14.85 5 . 2 ! 4.6: 0.8 2

I 6.9t 17.3: 10.85 9.15

10.4t 4.9: 2.4s 3.5c 8 . 6 ~ 8.07

r 1 . 0 6

9.24 1.53

8.32 4.68 6.66 8.66

8.56 I . 2 C

4.1 5 7.45 5.44

5.7 7 0.83 2.60 5 . 2 5 0.47 4.3 2 1.98 1.76 3.25 4.02 6.58 2.92

. 2 . I 2

2 .1 I

9.48 3.97 2.05

1.08

Mean Epoch

1869.5 1S62.t 1868.t 1864.1 1872.E 1868.;

1856.5 1863.c 1881.3 1882.1 1886.3 1874.1 1876.2 1862.8 1819.7 1879.2 1874.2 1894.2 1869.1 1868.9 1882.7 1 8 7 2 . 6 1867.5 1876.6 1876.6 1868.c 1865.1 1856.3 1870.4 1862.5 1860.9 1867.7 1877.8 1877.2 1884.6 1880.3

1872 .8

1815.5 1859.5

1870.2

1872.4 1878.0

1869.2 1865.4 1 8 7 7 . 0 r8i1.4 r870.7

r877.4 r869.8

r860.8 r873.0 r874.9 r868.8 r864.o !870.5

4stronomical Observatory, Azabu, Tokio, I 9 I o March 2 5 ,

- " Of

Ca - -

I

5 IC

c 15

2 i

1:

i

2 4

1 I 1

4c 1:

4 27

32 I t 1 6

I6

7 8

19 '3

I C

I C

Z C

Z C

7 16 1 4 16 '9

6 I 1

I 0

'3 I 0

2 1

' 5 5

' 7 13 '9 9 7

r6 [ I

r 2

[I 7

!9 10

9 I 6

Auwers- Bradley

+ 010 I

- 0.03: - 0 . 2 2 r

i-0.06( -0 .03~

- 0 . 0 3 ~

- 0 . 0 2

+o.oo< - 0.04 1

- 0 . 0 9 ~

+ O . O I ?

- 0 . 0 2 6

-0.13

-0.01~

to.007

-

t 0 . 0 5 4

t o . 0 1 7

-0.105

- 0.07 7

118 from other Au _ _ _ _ _ _ Groombr rhackera

- 0'10 I

+ O . O I (

- 0 . 0 3 ~ - 0.03:

- 0.05 1

- 0 . 0 9 ~ - 0 . 0 2 ~

-0.11:

-0.14;

+o.oog

+0.002

+ O . O I 2

-0.013

- 0.03 I

- 0 . 0 7 3

-0 .124

fo.00 I

- 0.09 I

-0.026

Lalande. Bossert

- 0 Y 2 2 c

-0.1 19

-0.134

-0.147

-0.410

- 0.105 - 0.065

rities

Porter ___

__ ~

- 0'12:

- 0 . 1 4

-0.39

-0.14 - 0.07

AG

-01007

-0.024

to.003

- 0 . 0 2

- 0.05