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Stars.

The sky is divided into 88 areas or constellations, whose names and boundaries were officially agreed on by a 1930 resolution of the International Astronomical Union. The constellation names are Latin, although several are derived from Greek.

Many of the constellation names are ancient, at least 2000 years old and, in some cases, more than 4000 years old. Amongst the oldest are the constellations of the zodiac, a band of stars along the ecliptic through which the Sun, Moon and planets move. Early stellar cartographers relied on mariners' accounts of the southern sky when inventing constellations that could not be seen from the north. It was only in the mid 1750s, when the French astronomer Lacaille visited Cape Town, that the southern sky was properly charted. He outlined and named many new constellations with names that are still used today.

Table 13 lists all the constellations that are entirely south of declination +30[degrees] and thus easily visible from Southern Africa. They are illustrated in the star maps on pp. 93-100. Within each constellation, the brighter stars are assigned letters of the Greek alphabet. Most of the brightest stars also have their own names, usually of Arabic origin. For example a Canis Majoris, otherwise known as Sirius, is the brightest star in Canis Major. Table 15 on page 79 lists the brightest stars visible from Southern Africa. When looking at these stars in the night sky, you will notice that they are not all white. For example, Rigel appears white while Betelgeuse has an orange hue. The colour of a star (see the last column of Table 16) is related to its surface temperature: red stars are cooler, blue stars are hottest.

The Southern Cross has found its way into the heraldic consciousness of a number of southern nations. In Australia, Crux appears on several state flags and badges, including the national flag, which accurately depicts all five stars. The national flag of New Zealand also shows Crux, as four red stars, edged with white. In an attempt to reflect their differing apparent magnitudes, alpha is shown as slightly larger and delta as slightly smaller than the other two stars,.

The unofficial flag of Christmas Island accurately depicts Crux, while the flags of Samoa and Papua New Guinea show a somewhat distorted Southern Cross. Both the national flag and the arms of the Federal Republic of Brazil include Crux.

Crux also appears on the coins of a number of countries (for some reason, coins of the northern hemisphere tend not to depict constellations). Brazilian, Australian and Western Samoan coins depict Crux (including epsilon Crucis) accurately. Several New Zealand coins show the Southern Cross rather crudely as four stars in a symmetrical pattern.

Oddly, Crux has made no impact on Southern African heraldry, which employs more earthbound symbols. Nevertheless, it does feature in the star-lore of the region. Some Bushmen knew the stars of Crux as "the giraffes", because these stars are big, like giraffes. The /Xam Bushmen knew the Pointers (alpha and beta Centauri) as male lions and the three brightest stars in Crux as female lions. In Sotho and Tswana tradition, a and p Crucis, together with the Pointers, made up Dithutlwa, the four giraffes. The Venda know them as Thuda. The Tswana see the brighter pair (the Pointers) as male giraffes, while the Sotho make them females.

Double stars

Single stars, such as our Sun, are the exception. The majority of stars are double (or multiple); the component stars, being gravitationally bound, move in elliptical orbits around a common centre of mass. Some stars, that seem to be located next to one another as seen from Earth, are not physically related and appear double only because of perspective. These are known as 'optical doubles'. Long-term observation of a true double star allows its orbit to be calculated, which in turn provides an opportunity for the masses of the stars to be determined. This knowledge is essential in the development of theories of stellar evolution.

Historically, the first "star" expressly mentioned by Ptolemy (c. 200 CE) as being double is the pair nu-1 and nu-2 Sagittarii. We now know that this pair is not a true double star, but an optical double. The modern definition of a double star may be credited to William Herschel, who published two double star catalogues with a total of about 700 objects in 1782 and 1785. This work was followed by other well known astronomers such as John Herschel (son of William); FGW von Struve (who catalogued 3134 objects) and his son, Otto; SW Burnham and others. In South Africa, the names Innes, Finsen and Van den Bos (at the Cape and Johannesburg), and Rossiter (at Bloemfontein) are connected with double star research. At present the US Naval Observatory is the leader in the field of double star research, and maintains the Washington Double Star Catalogue which currently lists more than 80 000 double stars.

Visual double stars are among the easiest of all astronomical objects to observe. A well-equipped observatory and a large telescope are not required. There are thousands of visual double stars that are within the range of small telescopes. Double stars can also be easily observed from locations suffering from moderate light pollution. There are many so-called "neglected" double stars that need to be confirmed. The only special instrumentation needed is an eyepiece to which a cross-hair has been fitted. Some means of accurately measuring the position angle and angular separation between the two stars is needed for more serious work.

This branch of astronomy offers a challenging alternative to "casual" astronomy and presents a unique opportunity for the observer to engage in real astronomical research, rather than just admiring the colour differences often found in a pair of doubles.

Variable Stars

Variable stars are stars that change brightness (most stars--including the Sun--vary in brightness if measured accurately). By studying their behaviour much can be learnt about their physical properties such as size, mass, luminosity, temperature, structure, composition and evolution. This information can then be used to understand other stars.

Over 30 000 variable stars are known and many thousands more are suspected to be variable. Professional astronomers are not able to gather data on the brightness changes of thousands of variable stars; there are simply too many stars. Amateur astronomers, using visual, photographic, photo-electric and CCD techniques, can make significant contributions to science by observing these stars. Some 2 000 variables are suitable for visual monitoring in the southern hemisphere. However, the number of active observers in this part of the world remains woefully small and fewer than 400 variables are at present being observed from Southern Africa.

Visual estimates of magnitude are made by comparing the variable with two or more comparison stars, shown on special charts, which have been prepared for each variable. The use of these charts is essential for accurate, standardized observations and intending new observers are therefore advised to obtain the necessary data by contacting the Director of the ASSA Variable Star Section.

The Section (established in 1914) disseminates incoming information amongst observers, and will forward (on request) the observations of individuals to various international variable star bodies, who combine the South African light estimates with those from other parts of the world. The resulting "light curves" and tables are made available to professional astronomers interested in investigating certain properties of the stars more fully. In recent years amateur observers have played an invaluable role by alerting the operators of orbiting satellite observatories whenever outbursts of certain eruptive variables are seen to occur, so that the orbiting observatories can be trained on the outburst for detailed study.

Did you know? ...

The coldest place in the Solar System is also close to home. NASA's Lunar Reconnaissance Orbiter recorded a temperature of -240[degrees]C inside a crater at the Moon's south pole where the Sun has never shone. This is 20[degrees]C colder than the previous record--Pluto.

What Albert Einstein said ...

* A man should look for what is, and not for what he thinks should be.

* Any man who can drive safely while kissing a pretty girl is simply not giving the kiss the attention it deserves.

* Everything should be as simple as it is, but not simpler.

* Problems cannot be solved by the same level of thinking that created them.

* Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either.

* Any man who reads too much and uses his own brain too little falls into lazy habits of thinking.

* Any fool can make things bigger, more complex, and more violent. It takes a touch of genius--and a lot of courage--to move in the opposite direction.

* It's not that I'm smart, it's just that I stay with problems longer.

Double Star Section

The ASSA Double Star Section, formed in 1999, aims to: encourage amateur astronomers worldwide to participate in double star observation; make available information on all aspects of double star observation; and to co-ordinate observations and to publish meaningful results in the interest of science. ASSA members who would like more information or would like to join the Section should contact: Lucas Ferreira, P.O.Box 7028, George, 6531. e-mail:[doublestar@assa.saao. ac.za] [www.lucastronomy.co.za]

What Thomas Edison said .....

* We now know a thousand ways how not to build a light bulb.

* Discontent is the first necessity of progress.

* There is no expedient way to which a man will not go to avoid the labour of thinking.

* To invent, you need a good imagination and a pile of junk.

Variable Star Section

The Variable Star Section of the ASSA exists for the purpose of encouraging observers and acting as a medium of communication. Prospective observers are welcome to contact the Director for assistance. New observers should supply brief details of their equipment. They will then be sent charts of a few easy objects and data on stars which may be observed with the equipment at their disposal. Contact: Chris Middleton, PO Box 67813, Bryanston, 2021. Tel: 082-920-3107 e-mail: [variable@assa.saao.ac.za]
Table 13. Constellations visible from Southern Africa

Constellation         Genitive              English name

Antlia                Antliae               Air Pump
Apus                  Apodis                Bird of Paradise
Aquarius              Aquarii               Water Bearer
Aquila                Aquilae               Eagle
Ara                   Arae                  Altar
Aries                 Arietis               Ram
Caelum                Caeli                 Chisel
Cancer                Cancri                Crab
Canis Major           Canis Majoris         Greater Dog
Canis Minor           Canis Minoris         Lesser Dog
Capricornus           Capricorni            Sea-Goat
Carina                Carinae               Keel
Centaurus             Centauri              Centaur
Cetus                 Ceti                  Whale
Chamaeleon            Chamaeleontis         Chamaeleon
Circinus              Circini               Compasses
Columba               Columbae              Dove
Corona Australis      Coronae Australis     Southern Crown
Corvus                Corvi                 Crow
Crater                Crateris              Cup
Crux                  Crucis                Cross
Delphinus             Delphini              Dolphin
Dorado                Doradus               Goldfish
Equuleus              Equulei               Little Horse
Eridanus              Eridani               River Eridanus
Fornax                Fornacis              Furnace
Gemini                Geminorum             Twins
Grus                  Gruis                 Crane
Horologium            Horologii             Clock
Hydra                 Hydrae                Water Monster
Hydrus                Hydri                 Small Water-Snake
Indus                 Indi                  Indian
Leo                   Leonis                Lion
Lepus                 Leporis               Hare
Libra                 Librae                Scales
Lupus                 Lupi                  Wolf
Mensa                 Mensae                Table (Mountain)
Microscopium          Microscopii           Microscope
Monoceros             Monocerotis           Unicorn
Musca                 Muscae                Fly
Norma                 Normae                Level
Octans                Octantis              Octant
Ophiuchus             Ophiuchi              Serpent-Holder
Orion                 Orionis               Orion (Hunter)
Pavo                  Pavonis               Peacock
Pegasus               Pegasi                Pegasus
Phoenix               Phoenicis             Phoenix
Pictor                Pictoris              Painter
Pisces                Piscium               Fish
Pisces Austrinus      Piscis Austrini       Southern Fish
Puppis                Puppis                Stern
Pyxis                 Pyxidis               Mariner's Compass
Reticulum             Reticuli              Reticle
Sagitta               Sagittae              Arrow
Sagittarius           Sagittarii            Archer
Scorpius              Scorpii               Scorpion
Sculptor              Sculptoris            Sculptor
Scutum                Scuti                 Shield
Serpens               Serpentis             Serpent
Sextans               Sextantis             Sextant
Taurus                Tauri                 Bull
Telescopium           Telescopii            Telescope
Triangulum Australe   Trianguli Australis   Southern Triangle
Tucana                Tucanae               Toucan
Vela                  Velorum               Sails
Virgo                 Virginis              Virgin
Volans                Volantis              Flying Fish
Vulpecula             Vulpeculae            Fox

Constellation         Abbr   RA   Dec   Sz.

Antlia                Ant    10   -35   62
Apus                  Aps    16   -75   67
Aquarius              Aqr    23   -15   10
Aquila                Aql    20   +05   22
Ara                   Ara    17   -55   63
Aries                 Ari    03   +20   39
Caelum                Cae    05   -40   81
Cancer                Cnc    09   +20   31
Canis Major           CMa    07   +20   43
Canis Minor           CMi    08   +05   71
Capricornus           Cap    21   -20   40
Carina                Car    09   -60   34
Centaurus             Cen    13   -50   9
Cetus                 Cet    02   -10   4
Chamaeleon            Cha    11   -80   79
Circinus              Cir    15   -60   85
Columba               Col    06   -35   54
Corona Australis      CrA    19   -40   80
Corvus                Crv    12   -20   70
Crater                Crt    11   -15   53
Crux                  Cru    12   -60   88
Delphinus             Del    21   +10   69
Dorado                Dor    05   -65   72
Equuleus              Equ    21   +10   87
Eridanus              Eri    03   -20   6
Fornax                For    03   -30   41
Gemini                Gem    07   +20   30
Grus                  Gru    22   -45   45
Horologium            Hor    03   -60   58
Hydra                 Hya    10   -20   1
Hydrus                Hyi    02   -75   61
Indus                 Ind    21   -55   49
Leo                   Leo    11   +15   12
Lepus                 Lep    06   -20   51
Libra                 Lib    15   -15   29
Lupus                 Lup    15   -45   46
Mensa                 Men    05   -80   75
Microscopium          Mic    12   -35   66
Monoceros             Mon    07   -05   35
Musca                 Mus    12   -70   77
Norma                 Nor    16   -50   74
Octans                Oct    22   -85   50
Ophiuchus             Oph    17   +00   11
Orion                 Ori    05   +05   26
Pavo                  Pav    20   -65   44
Pegasus               Peg    22   +20   7
Phoenix               Phe    01   -50   37
Pictor                Pic    06   -55   59
Pisces                Psc    01   +15   14
Pisces Austrinus      PsA    22   -30   60
Puppis                Pup    08   -40   20
Pyxis                 Pyx    09   -30   65
Reticulum             Ret    04   -60   82
Sagitta               Sge    20   +10   86
Sagittarius           Sgr    19   -25   15
Scorpius              Sco    17   -40   33
Sculptor              Scl    00   -30   36
Scutum                Sct    19   -10   84
Serpens               Ser    17   +05   23
Sextans               Sex    10   +00   47
Taurus                Tau    04   +15   17
Telescopium           Tel    19   -50   57
Triangulum Australe   TrA    16   -65   83
Tucana                Tuc    00   -65   48
Vela                  Vel    09   -50   32
Virgo                 Vir    13   -00   2
Volans                Vol    08   -70   76
Vulpecula             Vul    20   +25   55

Key: RA, Dec: Right Ascension (hours) and Declination (degrees)
of the approximate centre of the constellation. Sz: Size in rank
order out of 88 (Hydra=1,Crux=88).

Table 14. Constellation culminations

Date     Constellation

Jan 01   Canis Major
Jan 04   Gemini
Jan 05   Monoceros
Jan 09   Puppis
Jan 14   Canis Minor
Jan 18   Volans
Jan 30   Carina, Cancer
Feb 03   Pyxis
Feb 09   Hydra
Feb 11   Vela
Feb 21   Sextans
Feb 22   Antlia
Feb 24   Leo Minor
Feb 28   Chameleon
Mar 01   Leo
Mar 11   Ursa Major
Mar 12   Crater
Mar 28   Corvus
Mar 30   Crux
Mar 31   Musca
Apr 02   Coma
Apr 06   Centaurus
Apr 07   Canes Venatici
Apr 12   Virgo
Apr 30   Bootes
May 01   Circinus
May 09   Libra, Lupus
May 20   Corona Borealis
May 21   Apus, Norma
May 22   Triang. Australe
Jun 03   Scorpius
Jun 11   Ophiuchus
Jun 12   Ara
Jun 13   Hercules
Jun 21   Serpens
Jun 30   Corona Australis
Jul 01   Scutum
Jul 02   Lyra
Jul 05   Sagittarius
Jul 06   Telescopium
Jul 12   Aquila
Jul 13   Pavo
Jul 17   Sagitta
Jul 26   Vufpecula
Jul 29   Cygnus
Jul 31   Detphinus
Aug 04   Microscopium
Aug 05   Capricorn
Aug 09   Equuleus
Aug 13   Indus
Aug 25   Piscis Austrinus
Aug 26   Aquarius
Aug 28   Lacerta
Aug 29   Grus
Sep 01   Pegasus
Sep 17   Tucana
Sep 27   Pisces, Sculptor
Sep 29   Cepheus
Sep 30   Andromeda
Oct 05   Phoenix
Oct 15   Cetus
Oct 20   Aries
Oct 23   Triangulum
Oct 26   Hydrus
Nov 04   Fornax
Nov 07   Perseus
Nov 10   Eridanus
Nov 19   Reticulum
Nov 24   Horologium
Nov 30   Caelum, Taurus
Dec 07   Dorado
Dec 09   Auriga
Dec 13   Lepus, Mensa, Orion
Dec 15   Pictor
Dec 17   Columba
Dec 23   Camelopardalis

The nights on which the different constellations culminate, that
is, on which they reach the highest part of their course across
the sky.

Table 15. Brightest stars visible from S.Africa

Star                            RA            Dec
                                (J 2007.5)

[alpha] Eri       Achernar      01h           -57[degrees]   11' 56"
                                  37m 59.5s
[alpha] Tau       Aldebaran     04 36 21.1    +16            31 26
[beta] Ori        Rigel         05 14 53.9    -08            11 36
[gamma] Ori       Bellatrix     05 25 32.0    +06            21 21
[beta] Tau        Al Nath       05 26 46.0    +28            36 47
[epsilon] Ori     Alnilam       05 36 35.7    -01            11 51
[alpha] Ori       Betelgeuse    05 55 34.7    +07            24 29
[beta] CMa        Mirzam        06 23 01.8    -17            57 36
[alpha] Car       Canopus       06 24 07.1    -52            42 00
[gamma] Gem       Alhema        06 38 08.7    +16            23 32
[alpha] CMa       Sirius        06 45 28.5    -16            43 36
[epsilon] CMa     Adhara        06 58 55.2    -28            58 58
[delta] CMa       Wezea         07 08 41.8    -26            24 20
[alpha] Gem       Castor        07 35 04.5    +31            52 16
[alpha] CMi       Procyon       07 39 41.6    +05            12 20
[beta] Gem        Pollux        07 45 46.4    +28            00 27
[[gamma].sup.2]   Regor         08 09 45.8    -47            21 32
  Vel
[epsilon] Car     Avior         08 22 40.0    -59            32 02
[delta] Vel       Koo She       08 44 54.7    -54            44 12
[beta] Car        Miaplacidus   09 13 16.8    -69            44 53
[alpha] Hya       Alphard       09 27 57.4    -08            41 29
[alpha] Leo       Regulus       10 08 46.2    +11            55 49
[[alpha].sup.1]   Acrux         12 27 01.2    -63            08 26
  Cru
[gamma] Cru       Gacrux        12 31 35.2    -57            09 18
[beta] Cru        Mimosa        12 48 09.8    -59            43 47
[alpha] Vir       Spica         13 25 35.3    -11            12 01
[beta] Cen        Agena         14 04 21.5    -60            24 32
[alpha] Boo       Arcturus      14 16 00.2    +19            08 37
[[alpha].sup.2]   Rigel Kent    14 40 06.2    -60            52 00
  Cen
[[alpha].sup.1]   Rigel Kent    14 40 07.2    -60            51 55
  Cen
[alpha] Sco       Antares       16 29 52.1    -26            26 53
[alpha] TrA       Atria         16 49 27.9    -69            02 26
[lambda] Sco      Shaula        17 34 07.1    -37            06 31
[theta] Sco       Sargas        17 37 51.5    -43            00 07
[epsilon] Sgr     Kaus          18 24 40.2    -34            22 50
                    Australis
[alpha] Lyr       Vega          18 37 11.6    +38            47 28
[alpha] Aql       Altair        19 51 08.9    +08            53 19
[alpha] Pav       Peacock       20 26 14.2    -56            42 38
[alpha] Gru       Alnair        22 08 42,2    -46            55 28
[alpha] PsA       Fomalhaut     22 58 03.8    -29            34 56

Star              V        B-V

[alpha] Eri       +0.46    -0.16
[alpha] Tau       +0.85    +1.54
[beta] Ori        +0.12    -0.03
[gamma] Ori       +1.64    -0.22
[beta] Tau        +1.65    -0.13
[epsilon] Ori     +1.70    -0.19
[alpha] Ori       +0.50    +1.85
[beta] CMa        +1.98    -0.23
[alpha] Car       -0.72    +0.15
[gamma] Gem       +1.93    +0.00
[alpha] CMa       -1.46    +0.00
[epsilon] CMa     +1.50    -0.21
[delta] CMa       +1.84    +0.68
[alpha] Gem       +1.98    +0.03
[alpha] CMi       +0.38    +0.42
[beta] Gem        +1.14    +1.00
[[gamma].sup.2]   +1.78    -0.22
  Vel
[epsilon] Car     +1.86    +1.28
[delta] Vel       +1.96    +0.04
[beta] Car        +1.68    +0.00
[alpha] Hya       +1.98    +1.44
[alpha] Leo       +1.35    -0.11
[[alpha].sup.1]   +1.33    -0.24
  Cru
[gamma] Cru       +1.63    +1.59
[beta] Cru        +1.25    -0.23
[alpha] Vir       +0.98    -0.23
[beta] Cen        +0.61    -0.23
[alpha] Boo       -0.04    +1.23
[[alpha].sup.2]   +1.33    +0.88
  Cen
[[alpha].sup.1]   -0.01    +0.71
  Cen
[alpha] Sco       +0.96    +1.83
[alpha] TrA       +1.92    +1.44
[lambda] Sco      +1.63    -0.22
[theta] Sco       +1.87    +0.40
[epsilon] Sgr     +1.85    -0.03
[alpha] Lyr       +0.03    +0.00
[alpha] Aql       +0.77    +0.22
[alpha] Pav       +1.94    -0.20
[alpha] Gru       +1.74    -0.13
[alpha] PsA       +1.16    +0.09

The table above lists, in RA ordRA order,
2.0 and south of declination +40ation +40[degrees].

V: apparent (visual) magnitude. gnitude. B
positive values.

Table 16. Bright southern double stars

HR        WDS            RA                 Dec

531    01496-1041   01h 49m 57.2s   -10[degrees] 38' 58"
681    02193-0259    02 19 43.6          -02 56 38
681    02193-0259    02 19 43.6          -02 56 38
1856   05302-4705    05 30 21.9          -47 04 21
1931   05387-0236    05 39 07.4          -02 35 46

1931   05387-0236    05 39 07.4          -02 35 46
1983   05445-2227    05 44 46.6          -22 26 47
2736   07087-7030    07 08 40.9          -70 30 40
3207   08095-4720    08 09 45.8          -47 21 32
3315   08252-2403    08 25 23.2          -24 04 15

3582   08570-5914    08 57 09.4          -59 15 30
4180   10393-5536    10 39 36.4          -55 38 33
4257   10535-5851    10 53 48.1          -58 53 35
4369   11170-0708    11 17 21.0          -07 10 32
4621   12084-5043    12 08 45.0          -50 45 51

4898   12546-5711    12 55 02.3          -57 13 07
4993   13152-6754    13 15 45.9          -67 56 03
5171   13472-6235    13 47 42.7          -62 37 37
5531   14509-1603    14 51 17.7          -16 04 21
5646   15119-4844    15 12 27.6          -48 45 57

5683   15185-4753     15 19 3.5          -47 54 08
5984   16054-1948    16 05 52.5          -19 49 32
5985   16054-1948    16 05 52.8          -19 49 19
6027   16120-1928    16 12 25.9          -19 28 47
6077   16195-3054    16 20 01.3          -30 55 28

6115   16272-4733    16 27 44.2          -47 34 16
7476   19407-1618    19 41 09.1          -16 16 32
7776   20210-1447    20 21 25.9          -14 45 26
8140   21199-5327    21 20 23.8          -53 25 03
8576   22315-3221    22 31 55.8          -32 18 27

HR     Designation     Epoch        PA

531    ENG 8           2001    251[degrees]
681    H 6 1 Aa-C      2007         69
681    STG 1 Aa-D      1921        319
1856   DUN 21 AD       2000        271
1931   STF 762 AB-D    2002         84

1931   STF 762 AB-E    2003         62
1983   H 6 40 AB       1999        350
2736   DUN 42          1999        298
3207   DUN 65AB        2002        219
3315   S 568           2001         90

3582   DUN 74          2000         76
4180   DUN 95AB        2000        105
4257   DUN 102AB       2000        204
4369   BU 600 AC       2007         99
4621   JC 2 AB         1992        325

4898   DUN 126         2001         17
4993   DUN 131 AC      2000        331
5171   COO 157 AB      1991        321
5531   SHJ 186 AB      2002        315
5646   DUN 177         1999        143

5683   DUN 180AC       1999        129
5984   H 3 7 AC        2003         20
5985   H 3 7 CA        2003        200
6027   H 5 6 Aa-C      2003        337
6077   BSO 12          1998        319

6115   HJ 4853         1999        334
7476   HJ 599 AC       2003         42
7776   STFA 52 Aa-Ba   2001        267
8140   HJ 5258         2007        270
8576   PZ 7            1999        173

HR      sep      V     [DELTA]V

531    184.7"   4.69     2.12
681    122.6    6.65     2.94
681    148.5    6.65     2.65
1856   197.8    5.52     1.16
1931    12.7    3.76     2.80

1931    41.5    3.76     2.58
1983    96.9    3.64     2.64
2736    13.7    3.86     1.57
3207    41.0    1.79     2.35
3315    42.2    5.48     2.95

3582    40.1    4.87     1.71
4180    51.7    4.38     1.68
4257   159.4    3.88     2.35
4369    53.7    6.15     2.07
4621   268.9    2.51     1.91

4898    35.0    3.94     1.01
4993    58.3    4.76     2.48
5171    7.1     7.19     2.71
5531   231.1    2.74     2.45
5646    26.5    3.83     1.69

5683    23.9    4.99     1.35
5984    13.6    2.59     1.93
5985    13.6    4.52     1.93
6027    40.8    4.21     2.39
6077    23.5    5.55     1.33

6115    22.8    4.51     1.61
7476    44.7    5.42     2.23
7776   207.0    3.15     2.93
8140    7.1     4.50     2.43
8576    30.4    4.28     2.84

Key: HR: Number in the Bright Star Catalogue;
WDS: Washington Double Star Catalogue number;
V: apparent (visual) magnitude of the primary;
[DELTA]V: magnitude difference between primary
and secondary.

The Greek alphabet

[alpha]     alpha
[beta]      beta
[gamma]     gamma
[delta]     delta
[epsilon]   epsilon
[zeta]      zeta
[eta]       eta
[theta]     theta
[iota]      iota
[kappa]     kappa
[lambda]    lambda
[mu]        mu
[nu]        nu
[xi]        xi
[omicron]   omicron
[pi]        pi
[rho]       rho
[sigma]     sigma
[tau]       tau
[upsilon]   upsilon
[phi]       phi
[chi]       chi
[psi]       psi
[omega]     omega
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Publication:Sky Guide Africa South
Geographic Code:6SOUT
Date:Jan 1, 2011
Words:4030
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