Category : Science and Education
Archive   : ACE120-2.ZIP
Filename : DBLCOM.DAT

B00962
Eta Cassiopeiae
Orange and violet
The color contrast, best seen with good transparency, is very striking in a
350-mm at 145x, but not so in a 75-mm at 90x. This binary is only 6 parsecs
distant. --Mullaney, McCall
$
B02290
Gamma Arietis (Mesartim)
Bright white and gray
Easy in a 75-mm at 45x. --Mullaney, McCall
$
B02452
Alpha Piscium
Pale green and blue
A tight pair in small telescopes. Though both stars look white in a 350-mm
at 145x, other apertures give various color impressions. --Mullaney, McCall
$
B02477
Gamma Andromedae (Almach)
Orange, emerald?, blue
Finest colored double, orange and blue, and beautiful in all apertures. The
comes is also a very close binary, present separation 0.5 second, position
angle 110 degrees. It is difficult in a 350-mm refractor at 600x, but at that
magnification it is easy in a 750-mm reflector. --Mullaney, McCall
$
B02952
Iota Cassiopeiae
Yellowish, blue-white, blue-white
A fine triple, with blue-white comites 2.3 and 7 seconds from the yellowish
primary. It is somewhat difficult in telescopes smaller than a 150-mm.
--Mullaney, McCall
$
B03276
Gamma Ceti (Baten Kaitos)
Pale yellow and blue
Attractive, close pair. The color contrast is not obvious in a 75-mm, but
more definite with a 150-mm or a 350-mm. --Mullaney, McCall
$
B03584
Theta Eridani (Acamar)
Both white
Brilliant star. Though it lies half a degree outside a -40 degree
declination limit, it is one of the brightest doubles in the sky. It is easy
in a 75-mm at 45x, provided seeing is good at low altitudes. --Mullaney,
McCall
$
B04705
W (32) Eridani
Yellow and blue-green
The color contrast is very vivid in a 350-mm at 145x. --Mullaney, McCall
$
B06410
Beta Orionis (Rigel)
Blue-white and white
A blue-white supergiant star with a white, much fainter comes. Just
resolved in a 75-mm (150x), the pair is beautiful in a 350-mm (145x). The
comes has been reported by some astronomers as an exceedingly close binary. It
seems elongated at times in a 750-mm refractor at 550x. --Mullaney, McCall
$
B06655
Eta Orionis
Both white
Not easy in a 150-mm, or even a 250-mm, unless the seeing is good, and a
close pair in a 350-mm at 290x. --Mullaney, McCall
$
B06915
Lambda Orionis (Meissa)
Pale white and violet
An easy pair. --Mullaney, McCall
$
B06931
Theta Orionis (Trapezium)
All pale white
This beautiful multiple system is imbedded in the Orion Nebula. Six
components are visible in a 100-mm, and easy in a 250-mm at 160x. Many faint
red stars are seen in this region with a 750-mm reflector at 600x. Color
contrasts among the six stars are evident in a 150-mm, and easy in a 350-mm.
--Mullaney, McCall
$
B06937
Iota Orionis
White, pale blue, grape red
A fainter version of Beta Orionis (Rigel). A hint of dim nebulosity around
Iota is noted with 250-mm and 350-mm apertures. In the same field is the
double Struve 747 (magnitudes 4.25 and 5.50, separation 36 seconds).
--Mullaney, McCall
$
B07031
Sigma Orionis
A multiple star, three components being easily seen in a 75-mm, four with a
150-mm at 100x. The bright star has a very difficult, close (0.3-second) comes
making this a quintuple system. In the same field a little to the west is the
faint, coarse triple star Struve 761. --Mullaney, McCall
$
B07089
Zeta Orionis (Alnitak)
Topaz, yellow, light purple, gray
Has a bright, close comes and a distant, faint one. A difficult group
requiring good seeing even with a 350-mm. --Mullaney, McCall
$
B07557
Theta Aurigae
Very unequal, close pair; an interesting sight in a 350-mm, but difficult in
any telescope much smaller than 250-mm. --Mullaney, McCall
$
B08412
Beta Monocerotis
All yellow-white
Finest triple star. The components form a slender triangle of 10 seconds'
greatest extent. This group is easy in a 150-mm and a beautiful sight in a
350-mm. --Mullaney, McCall
$
B08804
12 Lyncis
A triple system, nice in a 150-mm. The secondary is 1.7 seconds distant at
position angle 90 degrees. --Mullaney, McCall
$
B08833
Alpha Canis Majoris (Sirius)
Brilliant white and yellow
The brightest star other than the sun dazzles the eye with its brilliance in
a 750-mm telescope. Under excellent sky conditions, the white-dwarf comes can
just be seen in a 200-mm at 280x. In a 350-mm at 145x, it is easy when the
seeing is good, but absolutely invisible in average or poor seeing. In a
750-mm reflector with a power of 600, the comes is not much plainer than in a
350-mm. --Mullaney, McCall
$
B09755
Delta Geminorum (Wasat)
Pale white and purple
Somewhat like Eta Cassiopeiae. --Mullaney, McCall
$
B10120
Alpha Geminorum (Castor)
Bright white, pale white, orange
The two very bright stars form a close binary. The faint third star, a
minute of arc away, is just visible in a 150-mm at 150x. Actually, Castor is a
sextuple system, since all three visible members are also spectroscopic
binaries. The Castor group is 14 parsecs from us. --Mullaney, McCall
$
B10281
Kappa Puppis
Both white
Resembles Gamma Arietis (Mesartim). It is easy in a 150-mm at 45x.
$
B11141
Zeta Cancri
Yellow, orange, yellowish (changing)
An attractive, but difficult, triple. Under average conditions, a 100-mm
shows only two components. The three are well-resolved in a 250-mm at 320x,
very easy in a 750-mm refractor at 550x. --Mullaney, McCall
$
B12080
Iota Cancri
Orange and blue
Like Beta Cygni (Albireo). It is easily split in a 150-mm at 45x.
--Mullaney, McCall
$
B14177
Gamma Leonis (Algieba)
Bright orange and greenish-yellow
A beautiful pair; a fine sight in a 75-mm. --Mullaney, McCall
$
B15537
Xi Ursae Majoris (Alula Australis)
Subdued white and grayish-white
A famous binary system with a period of 60 years. It forms a tight pair.
--Mullaney, McCall
$
B17027
Delta Corvi (Algorab)
Pale yellow and purple
A wide pair. The magnitude contrast is strong in a 350-mm at 145x.
--Mullaney, McCall
$
B17146
24 Comae Berenices
Orange and blue-green
Thes colors are vivid in larger telescopes. --Mullaney, McCall
$
B17270
Gamma Virginis (Porrima)
Both white
One of the best-known binary stars in the sky, with an orbital period cited
as 172 years. Its components are practically equal in brightness. Well seen
in a 75-mm. --Mullaney, McCall
$
B17556
Alpha Canum Venaticorum (Cor Caroli)
Flushed white and pale lilac
One of the best for small telescopes. Although some observers have seen
color contrast in this pair, to others both members look blue-white.
--Mullaney, McCall
$
B18133
Zeta Ursae Majoris (Mizar)
Brilliant white and pale emerald
The finest double star in the sky for most moderate instruments. Its
components are separated by 15 seconds; 4th-magnitude Alcor (g Ursae Majoris)
is 12 minutes distant. The field is excellent for comparing what the naked eye
can see with what a telescope reveals. Actually, Mizar-Alcor is a sextuple
system, since each of the three bright stars is also a spectroscopic binary.
The group is 27 parsecs from Earth. --Mullaney, McCall
$
B18155
g Ursae Majoris (Alcor)
The Mizar (Zeta Ursae Majoris)-Alcor field is excellent for comparing what
the naked eye can see with what a telescope reveals. Actually, Mizar-Alcor is
a sextuple system, since each of the three bright stars is also a spectroscopic
binary. The group is 27 parsecs from Earth. --Mullaney, McCall
$
B19856
Epsilon Bootis (Izar)
Pale orange and bluish-green
In good seeing, high power on a 75-mm shows the two beautifully-colored
diffraction discs nearly in contact. --Mullaney, McCall
$
B19991
Xi Bootis
Yellowish and red
A visual binary with a period of 150 years. Its colors are easy in a
350-mm. Xi Bootis is only 7 parsecs away from us. --Mullaney, McCall
$
B20725
Mu Bootis (Alkalurops)
A fine triple star, being a wide double whose fainter member is a 2-second
pair. Best view is with 145x on a 350-mm. --Mullaney, McCall
$
B20941
Delta Serpentis
Both white
Offers a fine pair in a 75-mm. --Mullaney, McCall
$
B21063
Zeta Coronae Borealis
Bright bluish and bright greenish
This double consists of nearly equal stars. The colors are delicate, but a
150-mm telescope or larger makes them definite. --Mullaney, McCall
$
B21593
Xi Scorpii
Pale white, pale yellow, gray
A triple, part of an unusual double system. A pair of 5th-magnitude stars
is 1 second apart, with a 7th-magnitude star 7 seconds off. In the same field
is the 12-second pair Struve 1999. All five stars are travelling through space
together. A 75-mm shows only four stars, but high power on a 150-mm splits the
close pair, thus showing all five. There are hints of color differences in a
350-mm (145x). The stars are rather scattered in a 750-mm reflector at 600x.
--Mullaney, McCall
$
B21609
Beta Scorpii (Graffias)
Pale white and lilac
Resembles Zeta Ursae Majoris (Mizar). It is a nice sight in small
telescopes. In a 350-mm the close and very difficult 10th-magnitude comes of
the primary could not be seen. Beta Scorpii and Alpha Scorpii (Antares)
provide an interesting dissimilarity in colors. --Mullaney, McCall
$
B21771
Nu Scorpii
A colorful double-double, a 2-second pair and a 1-second one about 42
seconds apart. A 75-mm telescope generally shows only a wide double, but
sometimes resolves one of the pairs. At high power, but with difficulty, a
150-mm shows Nu quadruple. A 350-mm at 290x makes the magnitude and color
contrasts evident, if seeing is good. --Mullaney, McCall
$
B22157
Alpha Scorpii (Antares)
Fiery red and emerald green
A beautiful unequal double star. Because it is only 2.9 seconds from the
bright primary, the companion is difficult in 150-mm and 200-mm telescopes
under average conditions, but in good seeing a 250-mm shows it will. On a fine
night with a 350-mm, this is perhaps the most attractive of all doubles. Even
when Antares is not resolved, the comes can be recognized as a green tinge to
one side of the red primary. The pair is a superb sight in a 750-mm refractor
at 550x. --Mullaney, McCall
$
B22351
16, 17 Draconis
Form a triple somewhat like Mu Bootis (Alkalurops), but the brighter
components are more nearly equal, and the primary has a close comes. Though
nice in a 150-mm, the system is best seen in a 350-mm at 45x. --Mullaney,
McCall
$
B23277
Alpha Herculis
Orange red and bluish-green
The colors are very intense, even in a 75-mm telescope. The brighter
comes is a semiregular variable. --Mullaney, McCall
$
B23294
Delta Herculis
White and purple
Two unrelated stars at different distances from Earth. --Mullaney, McCall
$
B23543
Rho Herculis
Attractive in small telescopes. --Mullaney, McCall
$
B23797
Nu Draconis
Both white
A pair of perfectly matched stars of equal brightness. This is one of the
few wide pairs that is attractive in larger telescopes. --Mullaney, McCall
$
B24538
95 Herculis
Pale red and pale green
A pair of bright stars, whose hues are delicate, but persistent in all
apertures. Both stars look white to many observers. --Mullaney, McCall
$
B24641
70 Ophiuchi
Yellow and red
A famous 88-year binary system. The colors are strong in a 75-mm (150x)
and 350-mm (145x). --Mullaney, McCall
$
B25466
Alpha Lyrae (Vega)
Both blue-white
Vega is a dazzling diamond. To the south lies the faint comes, rather
difficult in less than a 150-mm. In large refractors having a slight "blue
excess" in color correction, Vega is nearly pure blue, an amazing sight. Light
from this star takes 26 years to reach Earth. --Mullaney, McCall
$
B25666
Epsilon Lyrae
Yellow, ruddy, white, white
The well-known "Double-Double" rates as the finest multiple star. Both
close pairs (2.3 and 2.7 seconds) are just resolved by 100x on a 75-mm in
good seeing. Very easy with a 350-mm, which shows all four stars as white.
--Mullaney, McCall
$
B25991
Theta Serpentis (Alya)
Both white
An easy pair. --Mullaney, McCall
$
B26953
Beta Cygni (Albireo)
Orange and blue
A beautiful pair. These colors are much more vivid in a 75-mm than a
350-mm, as is often the case with bright stars. --Mullaney, McCall
$
B27347
Delta Cygni
White and blue-white
Offers a close binary with components very unequal in brightness. Can be
split in a 75-mm with good seeing; a splendid sight in a 350-mm at 145x; very
easy in a 750-mm at 550x. --Mullaney, McCall
$
B28965
Gamma Delphini
Yellow and pale green
A pair of bright stars, appears delicately colored in a 350-mm. --Mullaney,
McCall
$
B29509
61 Cygni
Both orange
A famous long-period binary star. Both components are easily split in a
75-mm. At a distance of only 3 parsecs, 61 Cygni is one of the nearest stars.
--Mullaney, McCall
$
B30118
Beta Cephei (Alfirk)
White and blue
Offers an unequal double to users of 75-mm telescopes. --Mullaney, McCall
$
B31398
Zeta Aquarii
Very white and white
Fine close binary. In a 100-mm the components appear in contact.
--Mullaney, McCall
$
B31419
Delta Cephei
Pale orange and blue
Easy in a 75-mm at 45x. The primary is a 5.4-day variable star, prototype
of the Cepheids. --Mullaney, McCall
@
Copyright 1983, 1984, 1985, 1986 AstroSoft, Inc. Excerpts from copyrighted
material are included by permission of Sky Publishing Corporation.