It is only relatively recently that I've taken an interest in double-star hunting.
It's fun and, at times, breathtaking! This documents double or multiple stars
I've seen.
The list below may be sorted! Initially it appears in a "career"
order, i.e. the order in which I've viewed them. However, you may sort the table
by constellation or by separation. Simply click on the "con"
or "sep" labels. Click again to reverse the sorted order.
| name |
con. |
sep. |
notes |
| ζ & 80 |
UMa |
708.5 |
aka Mizar & Alcor. Naked eye double. Alcor is yellow. |
| ζ |
UMa |
14.3 |
aka Mizar. Blue-white & blue-white. |
| θ * |
Ori |
8.8 |
aka Trapezium. Seen on a number of occasions. Stunning, particularly
if you can see the nebulosity. Recently tried to, within the city, with the SCT
and various eyepieces, to split the four main white stars, but was not successful.
Sep. ranges from 8.8 to 13.3. Feb '10, saw E star between A and B from city. Some report different colours! |
| ε |
Lyr |
210.5 |
The famous Double-Double. A fun yet challenging example. Good
for beginners and experienced observers. All white?Sep. for two pairs: 210.5 (or
3.5'). |
| ε1 |
Lyr |
2.1 |
All white? One pair of stars are the same colour; the other pair
are slightly different. |
| ε2 |
Lyr |
2.4 |
All white? One pair of stars are the same colour; the other pair
are slightly different. |
| α |
UMi |
18.6 |
aka Polaris. Funny, after all these years looking at Polaris
(to align scope). Yellow and blue, beautiful! |
| η |
Cas |
13.0 |
aka Achird. Yellow-light green and orange. Wow! Second viewing:
burnt yellow and dull orange. |
| β |
Cyg |
34.7 |
aka Albireo. The head of the swan. Warm yellow and blue-green.
It is very cool! |
| α * |
Gem |
4.2 |
aka Castor. The head of one of the twins. Two stars, bright white,
similar in magnitude, and very close together. Just see separation at 77x. Apparently,
there are 6 elements but even at 110x could only see the 2 main stars. Very nice! |
| γ |
Leo |
4.6 |
aka Algieba. Even though each star is a similar colour, a shimmering
gold perhaps, this double is stunning. One is slightly fainter than the other.
Viewed at 110x. On another occasion, spent more time: the main star is gold with
hints of light lime green; the companion is slightly white. |
| σ * |
Ori |
12.4 |
A wonderful grouping of many stars. There's a single "pointer"
star (SAO 132412). Then there's a cluster of 3 close stars in the middle—sigma
proper. Finally, 3 stars at the end, more widely separated (SAO 132399, 400, and
401). Creates overall impression of a narrow triangle. Viewed at 110x. All seemed
blue-white (from city limits). |
| ε |
Boo |
2.8 |
aka Izar. A challenging target requiring stable air to split
at 110x power. Main star is gold. The dimmer secondary is overwhelmed by the primary
so it is difficult to make out colour. It's tight even at 217x in RASC Toronto
Centre C14. At 391x, colours are white and pale blue. |
| α |
Leo |
176 |
aka Regulus. Viewed it at 110x. The main element was very white
blue while the companion is a very faint pale red orangey colour. Widely separated.
They were 1/8th of the field apart. |
| α |
UMa |
381 |
aka Dubhe. Interesting. The main star is bright yellow gold.
The companion is pale orange. It is a very wide pair. They are approx. 1/3rd of
the field apart at 110x. |
| α |
CVn |
19.3 |
aka Cor Caroli. Heard about this... finally viewed. Lovely at
110x. The main star is very white blue and the nearby star is a pale yellow green.
They are fairly close. |
| δ |
Boo |
104 |
The pair are about a 1/10th of the field from one another. Yellow
and pale blue green. |
| Σ1798 |
UMi |
7.5 |
(Sigma, Wilhelm Struve). Wow. Haas says "difficult but striking"
and she's not kidding. These two stars are very faint (Haas says magnitude 7.7
and 9.7). The brighter (ha) one is pale yellow; the fainter one is pale orange
/ brown. Quite close at 110x. |
| π1 |
UMi |
31.7 |
Yellow and orange with a medium separation, 1/40th of the field
at 110x. A nice pair. |
| 15 |
Aql |
39.1 |
A very interesting pair. They are dim so it is not easy to specify
the colours. The bright one seemed a dark, dark yellow; the companion looked a
ruddy rose red. |
| γ |
Del |
9.1 |
Bright yellow gold pair of stars, fairly tight at 77x. Similar
to γ Leo. |
| Σ2725 |
Del |
6.1 |
In the same field as γ Del, a similarly tight pairing.
However, these are dimmer. Dark orange and light pale blue. Evocative of ε
Lyra but more colourful and easier to spot. Pretty spectacular together... |
| π |
Boo |
5.5 |
A very close pair. Tough to make out the colours in unsteady
air. They are almost equal brightness. The bright one is perhaps light blue; the
dimmer one is pale orange. |
| ζ |
CrB |
6.3 |
A tight pair at 110x power. Pale green and pale blue? |
| Cr 399 |
Vul |
490 |
aka The Coathanger. Famous asterism. All white. Many of the stars
are 8 to 12' apart. Stumbled across this star hopping for Messiers! |
| 57 |
Aql |
35.9 |
A nice pair. But a bit off the beaten track. Almost equal in
magnitude. The brighter one is a pale lilac; the fainter star is pale yellow. |
| ο |
Cyg |
107 |
Wow. While the Omicron stars are not part of a single multi-star
system, they are still very neat. Bright central star is yellow fringed with orange.
This is 31 or Omicron-1. There is a pale blue star nearby. This is SAO 49338.
A more distant star (30) is white, between the other two in magnitude. Many faint
stars in the field. Power less than 77x would draw 32 or Omicron-2 into the field... |
| 61 |
Cyg |
31.1 |
A close pair. Yellow and pale green, perhaps. On another viewing,
at higher power, gauged both light gold. Almost equal brightness. Surrounded by
many faint stars. |
| γ * |
And |
9.7 |
aka Alamak. A close pair of yellow and blue stars, like a miniature
Albireo. About 1/3 of the separation of Albireo. Beautiful. Possibly more attractive. Haas shows a triple with the companion a very tight pair... |
| γ |
Ari |
7.5 |
aka Mesarthim. A rather close pair of bright white-blue-white
stars. Nearly identical magnitude and colour. On a subsequent viewing, I thought
they were yellow-white. Easy to split at 52x. They look like moth eyes! |
| 99 |
Aqr |
? |
Main star is yellow; companion is blue green. Noted as double
in PSA (star 99) but not in SA2K. Shows in Stellarium as "b2." Not noted by Haas. |
| 101 |
Aqr |
? |
Main star is blue white; companion is very pale grey. Noted as
double in PSA and SA2K. Shows in Stellarium as "b3." Not noted by Haas. |
| δ |
Ori |
52.8 |
aka Mintaka. A widely separated pair. Very attractive at low
power. Primary is white, perhaps a little yellow. The secondary is fainter and
a medium blue. |
| ζ * |
Ori |
2.6 |
aka Alnitak. I accidentally sighted the faint companion very
close to this star while going for δ. Oops. Similar colours but very different
brightnesses. Haas says it's a triple system. |
| ι |
Cnc |
30.7 |
A colourful, wide double surrounded by some fine white field
stars. A satisfying target in a faint constellation. Primary is straw yellow;
secondary is a bit fainter and medium blue. |
| ξ |
Boo |
6.3 |
A nice double at 110x. The main star is yellow; the seconary
is dark orange. |
| Σ1687 * |
Com |
12? |
Interesting double. There is a main bright yellow star. Nearby,
approx. 12" away is a blue star. Did I see two more faint companions to the
yellow? A quad?! Listed in Haas's book and Stellarium as 35 Com. Haas says it's a triple... |
| τ1 |
Hyd |
66.2 |
Pleasing double with warm yellow main star and pale orange companion.
Widely separated, estimated 1/15 the field at 110x (86"). |
Σ1291
or 57 |
Cnc |
1.5 |
Crazy close! Pale orange stars. Identical colour and brightness.
New record sep. |
| ι |
Leo |
1.7 |
Very tight pair. Main is white-yellow; companion dim blue. |
| δ |
Crv |
24.9 |
aka Algorab. Wide double. Pretty at low power. I think the main
is white or pale yellow. Companion: colourless...? Subsequent viewing: a pleasing,
easily-split double at low power, 52x. The main star is yellow white and bright;
dim companion is pale blue. Roughly estimate PA at 220°. |
| γ |
Vir |
0.4 |
aka Porrima. Wow! Identical bright white stars, extremely close.
With steady air, black gap seen, two separate points. New record! Uh, the 0.4
separation is an old figure. This fast-moving binary is separating. Some say they
are about 1.5" apart (for May 2009). Eric said 1¼" apart (for
Jun 09). I measured at CAO on 5 Jun 09 with Celestron Micro Guide without Barlow:
2.6 to 1.8". Measured on 22 Jun 09: sep 1.49 to 1.52; position angle 30°. |
| β |
Sco |
13.6 |
aka Graffias (or Acrab). The north pincer. Pretty double with
gold and pale blue-white stars. Viewed again but described different colours.
Jul 09: easily split with the 27mm in C14 (at 145x). It was widely split with
18mm (at 217x). Main star was white-blue whereas the companion was darker blue. |
| Σ1639 |
Com |
1.7 |
Main star yellow; companion quite pale. |
| 12 |
Com |
65 |
Wide pair. Yellow and orange. |
| δ |
Ser |
4.0 |
Tight pair. The main is white; the companion is straw-coloured. |
| λ |
Oph |
1.6 |
Marfik is another tight double. |
| ζ |
Sge |
1.6 |
The main star is pale yellow; the companion is faint, perhaps
orange or blue. It changes colour as you stare at it... |
| θ |
Ser |
22.3 |
aka Alya. A nice double, 2 identical white stars. Funny, the
notes in Haas's book say, "They seem like a pair of eyes..." The same
thought occurred to me. |
| κ |
Boo |
13.5 |
aka Asellus Tertius. Nice double. A bright white star and a pale
purple (OK, perhaps lilac) companion. Main star, at 217x in C14, is definitely
white. Companion shows a hint of colour at 391x. |
| ι |
Boo |
38 |
aka Asellus Secundus. Main is pale yellow; companion sheds medium
pale orange. |
| ο |
Cap |
21.6 |
Two equal pale blue white stars. Medium separation at low power. |
| π |
Cap |
3.2 |
aka Okul. Unable to split from CAO in Aug 2008! Tried again Jun
09. Jul 09: Two stars. A tight double. 18mm eyepiece in C14 helped to easily split.
One time I thought the main star was pale yellow white; another bright blue white.
The companion was faint, pale orange. Could still split, for certain, when air
steady, with the 27mm. But it was not obvious at 71x with the Tele Vue Plössl
50mm. The main star can overwhelm the companion. |
| ρ * |
Cap |
? |
I saw three stars. The main star is a bright yet pale yellow.
A fainter companion is yellow. At 90° there is a pale aquamarine star. Tried
again Jun 09. Should sketch this... |
| β |
Cap |
207 |
aka Dabih. I saw a bright yellow and bright blue star. There
was also a dark blue star nearby (not related). They form an isosceles triangle. |
| 72 * |
Peg |
0.5 |
Unable to split with SCT 14" at CAO in Aug 2008! Jul 09:
2:19. Tried again with 27, 18, 13, and 10mm. No joy. Split on 14 Aug 09 in moments
on clear seeing at 301 power. Very tight. Same colour, same brightness. |
| 78 * |
Peg |
0.8 |
Unable to split with SCT 14" at CAO in Aug 2008! Jul 09:
Hints though... Very possible. Even at low power with 27mm did not think perfectly
round. In 1999, the separation was 0.8". The period is 630 years. |
| λ * |
Ari |
15-20 |
Main star is yellow. Difficult to confirm companion colour. Blue
or dark orange? |
| Cr 69 |
Ori |
65 |
Pleasing grouping of stars in the head / neck region of Orion.
In a row. Perhaps a stretched out S-shape. All bluish in colour. Contains λ
Ori. |
| λ AB |
Ori |
4.3 |
aka Meissa. Tight double like Castor. Easily seperated at 111x
power. Main is pale yellow; companion blue-white. Very faint pale third star nearby.
Lies among many other field stars. Should look again—it's a quad system!
Viewed 2nd time and saw faint star near lambda A and B... More detail sketch made
on 3rd view. Confirmed: all 4 stars seen: A and B are tight, C is south, and D
is a degree away. |
| λ AC |
Ori |
28.0 |
aka Meissa. Viewed 2nd time and saw faint star near lambda A and B... More detail sketch made
on 3rd view. Confirmed: all 4 stars seen: A and B are tight, C is south, and D
is a degree away. |
| λ AD |
Ori |
78.0 |
aka Meissa. Quite far away. |
| ι |
Cas |
7.3 |
Part of a triple! At low power, 52x, you can just split the main
blue-white star from a pale dusty orange companion. The Position Angle of AB is
225° (my first estimates). Haas states wildly different colours than what
I saw! Feb '10: quickly estimated PA: 225 for AB pair. 230 according to Haas. |
| ι |
Cas |
2.9 |
Part of a triple! At 111x, I can split another pale, althought
slightly brighter, companion. The PA of AC is 90° (my first estimates). Feb '10: quickly estimated PA: 100 for AC pair. 115 according to Haas. |
| ζ * |
Cnc |
5.9 |
aka Tegmen (or Tegmine). Another triple! Pleasing at low power,
52x The main and companion stars were the same pale yellow colour. The companion
maybe had a hint of orange. |
| ζ * |
Cnc |
0.9 |
Another triple! At high power, the main star does not look round.
But could not definitely split, even at 500x. Looked like a figure-8. This close
pair was almost in-line with the distant companion, so while have almost the same
PA. Viewed from Toronto, High Park. |
| β |
Ori |
9.4 |
Fantastic! Rigel A is so bright, searing white-blue, it overwhelms
the view at low power. At higher power, you can easily spot the fainter companion
B. |
| β AB |
Mon |
7.1 |
At 55x, could see 2 stars, same colour. But companion star is
not round. A triple, woot! |
| β BC |
Mon |
2.9 |
At 111x, split companion! Now, all three stars are the exact
same colour. |
| ε |
Mon |
12.1 |
aka 8 Mon. A wide double at low power. Main star yellow; companion
dim yellow or pale orange. |
| α |
Her |
4.8 |
aka Rasalgethi. Lovely in the RASC Toronto Centre Celestron SCT
14. A brilliant shimmering orange star with pale blue companion. They seem relatively
tight but with the 18mm (217x) they are easily split. Tried measuring on Jun 09
with SCT 8" and Barlow: Sep. 6.9; PA 103°. |
| δ |
Cep |
40.6 |
Wow. Very pretty. Very wide pair, wide even at 36x. Yellow and
blue. The primary is a rather famous variable star... |
| α1 & α2 * |
Cap |
381.2 |
aka Algedi (or Al Giedi). Wow. One is a yellow-blue double. The
other is a single yellow star. Lots going on... Do a sketch next time. |
| α1 |
Cap |
46.0 |
One is a yellow-blue double (aka Algedi). |
| 16 |
Cyg |
39.1 |
A wide pair of faint white stars. Easily split at low power. |
| n/a |
Cyg |
- |
Fairy Ring. All stars are fairly faint. But there is an unmistakable
ring of double stars, yellow and blue, many aligned inward, i.e. pointing to the
centre. J2000 RA 20 03 40 dec +38 19 38. |
| α |
Lib |
231 |
aka Zubenelgenubi. Funny. Diane asked me, at the DDO Members'
Night, July 2009, if Zuben... was a double. I said I thought it was. I checked
my palmtop but I did not have it noted. But I was certain. I asked Gilles, with
his LX200 GOTO, to target it. We saw a very wide double (at 77x). The main star
was blue-white; the companion quite a bit fainter and white, if I remember correctly.
Haas disagrees with the colours: she says yellow and light grey. |
| 39 |
Boo |
2.7 |
Split in 27mm on C14 but tight. Tried 13mm but too blurry. Same
golden colour? Perhaps secondary is white or very pale blue. Almost equal in brightness.
The 18mm offered a good view. But it made the colours look similar. |
| σ |
CrB |
7.0 |
A nice double star. Same colours, both pale gold. Phil said "whitish,
the bright one is slightly more yellow." Similar magnitudes. |
| μ |
Cyg |
1.9 |
Very tight. Nice. Similar colours. Perhaps there's a hint of blue
in the secondary (oops, I forgot to note the primary's colour). Phil suggested
they were a full magnitude different. Haas says 1.5. Good view at 300x. |
| ζ |
Aqr |
2.0 |
aka Sadaltager (or Altager). Overall rather bright. A very tight
double. Nearly equal in brightness and colour. The main is pale yellow; the secondary
is pale white. |
| 12 * |
Aqr |
2.5 |
A nice double. Just able to split at 145x; easily split at 217x.
Different brightness. I thought exactly the same colour! S&T and Haas say
very different. Returned Aug 09. Colours seem pale yellow and dark yellow in large
aperture but yellow and white in small aperture. |
| 95 |
Her |
6.3 |
A gold and blue-white combination, widely separated. Smyth says:
"light apple green; cherry red." What?! |
| 16-17 |
Dra |
90 |
I can see how 16 and 17 Draconis would be a good bino double.
Similar colours and brightness. Nice. |
| 17 |
Dra |
3.0 |
Very cool at 217x. Easily split at 145x. Similar colours and brightness.
17 B is a little dimmer, perhaps with a touch of yellow. |
| μ |
Dra |
2.3 |
aka Alrakis. Ha! Exact same brightness and colour. Exact! A nice,
tight double. |
| ζ |
Lyr |
43.8 |
How about that... An easy wide double near ε. Good to show
before the Double-Double? Main was white-beige; compansion was pale yellow lime. |
| STT 525 * |
Lyr |
45.1 |
aka WDS SHJ 282 or OΣ 525. Nice wide double. Classic colours:
pale yellow and pale blue. Haas says it's a triple. |
| ν |
Dra |
63.4 |
aka Kuma. At long last. Nice easy wide double. Same brightness.
One is white; the other has a hint of yellow. aka Dragon's Eyes. Very good. |
| ψ |
Dra |
30.0 |
Might be a good candidate for an every-season double star list.
Wide pair. Surprisingly bright stars. Main is bright yellow; the companion? Dark
yellow or yellow with a hint of orange. Interesting. |
| 40-41 |
Dra |
18.6 |
Another nice wide double. Nearly equal colour and brightness.
Surprisingly close to Ursa Minor. Might this be another good year-round double.
Not very colourful... |
| Σ 1694 |
Cam |
21.5 |
A wide double, equally bright stars. They have the same white
colour it seems. Again, not too exciting, although they can likely be seen year-round.
Listed incorrectly in Haas's book as 32. 32H is a correct alternate. Listed incorrectly
in Sky & Telescope's summer doubles list as 35! |
| 11-12 |
Cam |
179 |
Interesting. Bright star is blue white; companion is a deep orange.
Fantastic colour in the companion. There were widely separated. Now this would
be a good one to show off... |
| α |
Psc |
1.9 |
aka Alrescha. Wow. Very tight double. Two pure white bright stars,
the same colour. Companion is about 1/2 or 1 mag different. |
| ζ |
Psc |
22.8 |
Bright stars. The main is yellow. The companion is
slightly redder. |
| ψ1 |
Psc |
30 |
Equally bright, pale yellow stars with a medium separation. There's
a nearby blue star at a 120 angle to the yellow stars. It has a sep. twice that
of the yellows. View with ψ2 and &psi3 using binoculars. |
| φ |
Cas |
135.3 |
A wide double atop open cluster NGC 457. Pale white stars. |
| Σ 163 |
Cas |
~33 |
Wow. Orange primary and very faint blue (maybe aqua) companion.
Wide pair, separation similar to Albireo. Both are faint. |
| ψ * |
Cas |
2.6 to 22.4 |
Reminds me of Polaris where main star is easy to spot but companion,
while widely separated, is very faint. Haas says this is a triple so I plan to
revisit... |
| τ |
Oph |
1.5 |
Very tight double (at 145x). Almost equal brightness, same colour:
pale yellow white. Noted by Haas as 69. |
| 70 |
Oph |
4.7 |
Bright stars. Main is light gold. Companion fainter, slightly
darker. Very pretty at 145x. |
| ρ |
Her |
4.1 |
Nice double at 145x. Same colour? White with hint of blue. Slightly
different mag, approx. 1.0 difference. |
| μ |
CMa |
3.2 |
Very tight double. Two gold stars. Estimated PA 310°. |
| φ2 |
Cnc |
5.2 |
Attractive double at low power. Two equally bright, identically
coloured, blue white stars. Not far from Pollux. Estimated PA 225°. |
| 14 AC * |
Ari |
106.7 |
Wide double chosen to perform formal measurement. Didn't realise it was a triple. Found AC pair to be a very wide double, pale yellow and pale blue. Sep. based on direct measurement on CMG LS: 105.4. PA based on LCS exit angle: 261. Results with Teague's "advanced" method: sep. 103.9; PA 281. |
 |
|
|
|
* To be revisited, so to confirm details, perhaps sketch.
Total viewed: 105.
