Star Lore Of All Ages/Appendix

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4113020Star Lore Of All Ages — Appendix1911William Tyler Olcott

Appendix

APPENDIX

THE BRIGHTEST STARS VISIBLE IN LATITUDE 40°N.[1]

STAR MAGNITUDE
The Sun —25.4
Sirius —1.58
Vega 0.14
Capella 0.21
Arcturus 0.24
Rigel 0.34
Procyon 0.48
Altair 0.89
Aldebaran 1.06
Pollux 1.21
Spica 1.21
Antares 1.22
Fomalhaut 1.29
Deneb 1.33
Regulus 1.34
Castor 1.58
ε Canis Majoris 1.63
ε Ursæ Majoris 1.68
Bellatrix 1.70
λ Scorpii 1.71
ε Orionis 1.75
β Tauri 1.78
α Persei 1.90
ζ Orionis 1.91
η Ursæ Majoris 1.91
γ Geminorum 1.93

LIGHT-GIVING POWER OF THE STARS, SUNLIGHT BEING EQUAL TO UNITY[2]
SIRIAN STARS SOLAR STARS
Procyon 25 Aldebaran 70
Altair 25 Pollux 170
Sirius 40 Polaris 190
Regulus 110 Capella 220
Vega 2050 Arcturus 6200

The total light of the stars is estimated as equal to 1/80 of that of the full moon.


NEAREST LUCID STARS IN THE NORTHERN HEMISPHERE
Distance in Light Years according to
Star Name Magnitude Todd Russell Gore Yale Univ. Young Newcomb
Sirius -1.6 8.5 8.6 9 8.6 8.0
τ Ceti 3.6 9.7 10.2 10.0
Procyon 0.5 12.0 10 10 9.8 10.9 10.0
61 Cygni 5.6 7.2 11.1 8.0 7.3
Altair 0.8 16.0 14 14.1 13.6 14.0
Vega 0.1 27.0 40 21.7 29.0
Aldebaran 1.0 32.0 32 28 29.6 29.0
Capella 0.2 32.0 40 34 36.0
Polaris 2.1 47.0 46 44 54.0
Arcturus 0.2 160.0 160 108.0
β Cassiopeiæ 2.4 032 21.0

Of the fainter stars in the northern hemisphere the 7.4 magnitude star Lalande 21185 is probably the nearest star to the earth. The average distance as estimated by different authorities is 7.3 light years.

The distance of the first magnitude star α Centauri in the southern hemisphere, probably the nearest star to the earth, is given by all authorities as 4.3 light years. This distance is better realised if we adopt Prof. Young's comparison: If the distance from the earth to the sun were 215 ft. the distance from the earth to α Centauri would be 8000 miles.

On the scale measured at Yale University the mean distance of stars of the first magnitude is 36.5 light years, second magnitude stars 58 light years, and those of the third magnitude 92 light years.

NUMBER OF THE STARS[3]
SeventhFirst Magnitude 20
SeventhSecond {{{1}}} 65
SeventhThird {{{1}}} 200
SeventhFourth {{{1}}} 500
SeventhFifth {{{1}}} 1400
SeventhSixth {{{1}}} 5000
Seventh {{{1}}} 20000
SeventhEighth {{{1}}} 68000
SeventhNinth {{{1}}} 240000
SeventhTenth {{{1}}} 720000 1,055,185

The lucid, or naked-eye, stars comprise the first six magnitudes.

A 5″ telescope reveals stars down to the 12th magnitude, and Prof. Ritchey of the Mt. Wilson Observatory using the new 60″ reflector has photographed by four-hour exposures stars probably as faint as the 20th or 21st magnitude. It has been estimated that the total number of stars within our ken photographically speaking is possibly 125 million.


Oldest Stars
(Red)
Next in Order
(Yellow)
Youngest Stars
(White)
Antares Our Sun Sirius
Aldebaran Capella Deneb
Betelgeuse Pollux Procyon
Arcturus Spica
Altair
Regulus


Periodic Comets
Name Last Perihelion Period in Years Next Return
Encke Sept. 15, 1901 03.3
Brorsen Feb, 25, 1890 05.45 1911
Tempel Swift June 5, 1897 05.54 1913
De Vico Swift Apr. 27, 1901 06.4 1914
Tempel II Oct. 04, 1898 06.5 1911
Finlay Feb. 17, 1900 06.5 1913
Wolf July 05, 1898 06.8 1912
Holmes Apr. 29, 1899 06.8 1913
Faye Jan. 23, 1881 07.5 1911
Tuttle May 05, 1899 13.6 1913
Pons Brooks Jan. 26, 1884 71.5
Olbers Oct. 09, 1887 72.6
Halley May 17, 1910 76


Proper Motion of the Stars
(The angular motion across the line of sight.)
Star Name Speed in Miles per Second
Pritchard Young
β Cassiopeiæ 10
α Cassiopeiæ 02
61 Cygni 35 37
Polaris 02.5 01.8
α Arietis 08
α Persei 01
Elkin
Aldebaran 04 05.1
Capella 11
Sirius 09 10.1
Procyon 13 12.2
Pollux 27
Regulus 08
Vega 31 07.1
Altair 09 08.0
Miss Clerke Newcomb
Arcturus 375 200 to 300


Secchi's Spectroscopic Star Types
Characteristics Star Names
Type I. Sirian Stars
(blue or white)
Broad, intense, dark hydrogen lines

Sirius
Vega

Altair and perhaps more than half of all the stars
Type II. Solar Stars
(yellowish like sun)
Fine, dark, metallic lines

Capella
Arcturus

Type III.
Orange and reddish stars
Many dark bands

α Herculis
Mira
Antares

A majority of the variable stars
Type IV.
Blood red in tint
Dark bands or flutings, the reverse of Type III. as to shading
About 50 stars of this type
Type V. Bright lines

Number about 70

Situated near the middle of the Galaxy


Scintillation
Secchi's type Mean Scintillation
III 87
III 79
III 59

Scintillation is most pronounced in January and February, and magnetic storms and violent scintillations are absolutely coincident in point of time.


Stars Approaching the Earth
Star Name Speed in Miles per Second
Potsdam Todd[4] Greenwich Vogel
α Arictis 11.7 09.2
γ Leonis 25.1
Spica 14 10.6 17 09.2
Altair 23.9 27 23.7
Polaris 16.3 16
Algol 02.3 02
Arcturus 45 04.6
Vega 34 09.7
Deneb 36 05.1
Pollux[5] 33
Sirius 09.7
Procyon 07 05.5
Castor 18.4


Stars Receding the Earth
Star Name Speed in Miles per Second
Potsdam Todd[4] Vogel Greenwich
Aldebaran 30 31.1 30.1 31
Rigel 39 13.6 10.1 18
Betelgeuse 17.6 28
α Coronæ 20.3
Capella 17 15.2 23
ε Orionis 34 35


Famous Temporary Stars
Date Appearing in the Constellation
134 b.c. Scorpio The star of Hipparchus
123 a.d. Ophiuchus
386 Sagittarius
389 Aquila near Altair
393 Scorpio
1012 Aries
1203 Scorpio
1230 Ophiuchus
1572 Cassiopeia Tycho's Star
1604 Ophiuchus Keplers's Star
1670 Vulpecula
1848 Ophiuchus
1860 Scorpio
1866 Corona Borealis
1876 Cygnus
1885 Andromeda
1891–92 Auriga


Famous Variable Stars
Star Name Period in Days Range in Magnitude Type
ο Ceti 331 1.7 to 9.5 Mira
R. Leonis 313 5.2 to 10.0
β Persei 002 7/8 2.3 to 3.5 Algol
ζ Geminorum 010 1/7 3.7 to 4.5
δ Libræ 002 1/6 5.0 to 6.2
χ Sagittarii 007 4.0 to 6
β Lyræ 12.9 3.4 to 4.9
α Herculis 90± 3.1 to 3.9 Irregular

  1. With the exception of the estimate of the sun's magnitude the list is taken from the Harvard Observatory Catalogue.
    Other results for the stellar magnitude of the sun are as follows:
    Wollaston: —26.6
    Bond: —25.8
    Zöllner: —26.6
    The sun gives us: 10,000,000,000 times the light of Sirius.
  2. From calculations made by Mauder.
  3. From Todd's Astronomy.
  4. 4.0 4.1 From Todd's Astronomy.
  5. According to Allen Pollux is receding from the earth at a rate of 1 mile per second.