21441+2845 STF 2822 AB (Mu1 Cyg)
21h 44m 08.57s +28° 44' 33.4" P.A. 325.00 sep 1.6 mag 4.75,6.18 Sp F6V+G2V dist. 22.24 pc (72.55 l.y.)
Coord 2000
21441+2845
Discov num
STF2822
Comp
AB
Coord arcsec 2000
21 44 08.57 +28 44 33.4
Date first
1777
Date last
2020
Obs
735
Pa first
108
Pa last
324.9
P.A. Now (θ)
325.5°
Sep first
11.0
Sep last
1.59
Sep. Now (ρ)
1.472"
Mag pri
4.75
Mag sec
6.18
delta mag (ΔM)
1.43
Spectral class
F6V+G2V (yellow-white/yellow)
Pri motion ra
+260
Sec motion ra
+260
Pri motion dec
-243
Sec motion dec
-243
Notes
N
O
(See Notes, Orbital solution)
This double is physical.
21441+2845 SYSTEM COMPONENTS
Show
name
SAO
coord
wds_name
last
obs
pa
sep
mag1
mag2
d_mag
orb
current
Show
Mu1 Cyg
89940
21 44 09 +28 44 33
STF 2822 AB
2020
735
325
1.6
4.75
6.18
1.43
Y
<===
Show
89940
21 44 09 +28 44 33
STF 2822 AC
2012
16
292
76.6
4.75
12.93
8.18
Show
89940
21 44 09 +28 44 33
STF 2822 AD
2019
56
43
197.0
4.75
6.94
2.19
Show
89940
21 44 09 +28 44 33
FYM 25 AF
2012
3
72
111.5
4.75
12.64
7.89
Show
89940
21 44 09 +28 44 33
FYM 25 AG
2012
3
73
168.1
4.75
13.77
9.02
Show
89944
21 44 08 +28 44 35
STF 2822 BD
2012
24
45
196.7
6.18
6.94
0.76
Show
89944
21 44 19 +28 46 54
ES 521 DE
2015
7
286
17.5
6.94
13.13
6.19
Show
89944
21 44 19 +28 46 54
FYM 25 DG
2012
3
164
89.6
6.94
13.77
6.83
Septuple system
7 estimated visually detectable stars in this system
OTHER CATALOGS AND DESIGNATIONS
Name
Mu1 Cyg
Constellation
Cygnus
SAO
89940
HIP
107310
Tycho2
2201-02078-1
HD
206826
HR
8309
GC
30438
ADS
15270
GL
Gl 836.6A
BD
BD+28 4169
Bayer
Mu 1 Cygni
Bayer name
Mu1 Cyg
Flamsteed
78 Cygni
Flamsteed name
78 Cyg
Distance
22.24
Distance ly
72.55
Bayer greek
μ1 Cyg
ORBITAL ELEMENTS
Period (P) 692.0588y ± 94.1386
Periastron (T) 1958.2452y ± 0.836
Semi-major axis (a) 4.65541a ± 0.43627
Eccentricity (e) 0.61798 ± 0.04089
Inclination (i) 75.219° ± 0.366
Longitude of periastron (ω) 143.214° ± 1.759
Node (Ω) 110.96° ± 0.411
Notes n
Reference Izm2019
Equinox
Last observation 2015
Grade 3 (1=Definitive, 9=Indet.)
label
theta
rho
2000
306.9
1.891
2001
307.6
1.876
2002
308.2
1.860
2003
308.9
1.844
2004
309.5
1.827
2005
310.2
1.810
2006
310.9
1.792
2007
311.6
1.775
2008
312.4
1.756
2009
313.1
1.738
2010
313.9
1.720
2011
314.6
1.701
2012
315.4
1.682
2013
316.2
1.663
2014
317.1
1.644
2015
317.9
1.625
2016
318.8
1.605
2017
319.7
1.586
2018
320.6
1.567
2019
321.5
1.548
2020
322.5
1.529
2021
323.4
1.510
2022
324.4
1.491
2023
325.5
1.472
2024
326.5
1.453
2025
327.6
1.435
2026
328.7
1.417
2027
329.9
1.400
2028
331.0
1.382
2029
332.2
1.365
2030
333.5
1.348
Note: Theta is PA, Rho is Sep. For yearly orbits, data refer to Jan 1st.
Measures: green=micrometric, blue=interferometric, purple=photographic
WDS 21441+2845 STF 2822 AB (Mu1 Cyg) : NOTES
discov_num
notes
refcode
STF2822
mu Cyg. The A component is a double-lined spectroscopic binary.
AB: H III 15. D is the principal component of ES 521.
AC and AD: Optical pairs, based on study of relative motion of the
components using the method of apparent motion parameters.
Kiy2008
AB: H 3 15.
MEv2010
ES 521
DE: D is SB2
Tok2014d
FYM 25
DG pair initially listed incorrected as DH.
FyM2014b
STF2822
AC: Rectilinear solution by Friedman et al. (2011).
USN2011a
REFERENCES
refcode
metd
author
reference
FyM2014b
C -
Fay, M.
.
FyM2014b
private communication
Izm2019
orb u
Izmailov, I.S.
2019AstL...45...30I
Izm2019
Ast. Lett. 45, 30, 2019
Izm2019
(Orbital elements from weighted solutions used when available (Table 2),
Izm2019
unweighted elements (Table 1) used for remaining 29 systems.)
Kiy2008
-
Kiyaeva, O.V., Kiselev, A.A. & Izmailov, I.S.
2008SvAL...32..405K
Kiy2008
SvAL 34, 405, 2008
MEv2010
-
MacEvoy, B.
...................
MEv2010
private communication, 2010 (see http://www.handprint.com/ASTRO/index.html)
Tok2014d
E2 -
Tokovinin, A.
2014AJ....147...86T
Tok2014d
AJ 147, 86, 2014
USN2011a
lin -
Friedman, E.A., Mason, B.D., & Hartkopf, W.I.
2011IAUDS.175....1F
USN2011a
Inf. Circ. 175, 1, 2011
DISCOVERER
idgroup
discov
author
1
ES
Espin, T.E.
96
STF
Struve, F.G.W.
WDS HISTORIC DATA
coord_2000
discov_num
comp
epoch
obs
pa
sep
mag_pri
mag_sec
spectr
notes
coord_arcsec_2000
21441+2845
STF2822
AB
2006
695
312
1.8
4.75
6.18
F6V G2V
NOD
214408.57+284433.4
21441+2845
STF2822
AB
2007
698
312
1.8
4.75
6.18
F6V G2V
NOD
214408.57+284433.4
21441+2845
STF2822
AB
2008
703
315
1.9
4.75
6.18
F6V G2V
NOD
214408.57+284433.4
21441+2845
STF2822
AB
2009
704
314
1.8
4.75
6.18
F6V G2V
NOD
214408.57+284433.4
21441+2845
STF2822
AB
2010
718
313
1.7
4.75
6.18
F6V G2V
NOD
214408.57+284433.4
21441+2845
STF2822
AB
2011
722
316
2.0
4.75
6.18
F6V G2V
NOD
214408.57+284433.4
21441+2845
STF2822
AB
2012
723
316
1.6
4.75
6.18
F6V G2V
NOD
214408.57+284433.4
21441+2845
STF2822
AB
2013
735
318
1.7
4.75
6.18
F6V G2V
NOD
214408.57+284433.4
21441+2845
STF2822
AB
2014
708
319
1.7
4.75
6.18
F6V G2V
NOD
214408.57+284433.4
21441+2845
STF2822
AB
2015
713
319
1.7
4.75
6.18
F6V+G2V
NO
214408.57+284433.4
21441+2845
STF2822
AB
2016
720
321
1.8
4.75
6.18
F6V+G2V
NO
214408.57+284433.4
21441+2845
STF2822
AB
2017
725
322
1.7
4.75
6.18
F6V+G2V
NO
214408.57+284433.4
21441+2845
STF2822
AB
2018
726
321
1.6
4.75
6.18
F6V+G2V
NO
214408.57+284433.4
21441+2845
STF2822
AB
2019
729
322
1.6
4.75
6.18
F6V+G2V
NO
214408.57+284433.4
21441+2845
STF2822
AB
2020
734
325
1.6
4.75
6.18
F6V+G2V
NO
214408.57+284433.4
If you need more information about this double, apply for a
data request form to the WDS.
WDS 21441+2845 STF 2822 AB (Mu1 Cyg) : VISUAL OBSERVATIONS REPORTS
Show
date
username
difficulty
separation
pa_estim
interest
notes
Show
23/08/02
oldscope
mean difficulty
separated
do not miss it!
Gear: Antique 1903 4-1/2” [~115mm] f/15 Brashear refractor (which made the cover of August Sky & Tele), hand driven EQ; Baader prism diagonal and Baader Hyperion 8-24 Zoom, plus a Televue 3-6 Zoom. This is a lovely kit for easy visual observing. Zoom eyepieces make double star viewing a real pleasure as you can get to the correct magnification very quickly without swapping a lot of eyepieces. The Baader zoom is exquisite with its wide field and superb optics. Its single drawback is that it is not parfocal. The Televue is almost perfectly parfocal, but its field of view is considerably narrower. It also has outstanding optics. Between the two, it gives me a range of magnification from 71X to 572X! The practical limit for the Brashear is 450X so I was covered for all seeing conditions. Oh, and I use an adjustable observing chair. Comfort is paramount.
Site: My backyard in Forest Hills, Queens, NYC. Bortle 10 (ughh!) and surrounded by 3 story houses, but a clear horizon from about 25 degrees and higher in the East and South. “It’s complicated.”
Conditions: 70F/21C, holding steady. 58% humidity, -0- clouds, -0- wind, transparency est. 7/10 (lightly hazy with a halo easily seen around the moon. The 97% waning moon was initially behind the neighbor’s house but rose into full view at 17deg 30min around 23:15 local time. Seeing (spoiler alert 9.5/10).
Observation:
Mu1 Cyg, 23:10-23:20 local time. It was perfectly placed at +55○ altitude. At Mag 4.49 (some listings have it at mag 4.6, but that is only the primary), it is too faint for me to see naked eye in the glow of NYC. But it shows up easily enough in my little finder, and it was easy to identify as it has a bright-ish nearby star, HIP107326 at mag 6.85. Centering on the brighter of the two stars in the finder, Mu1 Cyg was in the field of view of the Hyperion zoom at low power. I immediately dialed it down to 8mm, 214X and noticed that it was elongated. OK, found it! And the seeing looked encouraging. Swapping in the Televue 3-6 Zoom, at 6mm (286X), the double now separated cleanly. And it was rock-steady in the eyepiece. The primary’s Airy disk was sharp. One diffraction ring was visible in the light pollution/moon glow/light haze background. But the B component was clearly visible and well separated. The separation is listed as 1.51 in Stelle Doppie, but digging deeper, it was last measured in 2019 by Izmailov and the current Washington Double Star orb6 ephemeris lists it at 1.472 arcseconds for 2023, with a quality degree of 3, which is pretty good.* What makes this a tricky double is that the B component is sitting smack in the diffraction ring. I dialed the eyepiece to 5mm (343X) and clearly saw this. I also noticed that both Airy disks were still hard edged and dead steady. The seeing was superb and the Brashear lens had reached perfect thermal equalization with the unchanging temperature. I got the sense that this was a rare night. It is not often that I’m tempted to increase the magnification to 429X, using the 4mm setting, but last night the seeing held up and the view of this double was sublime. The color of the mag 4.69 primary Airy disk showed a very distinct pale creamy tinge and the fainter mag 6.12 secondary was a definite blue-gray. The seeing was so good that the diffraction ring was complete all around, not breaking up, and uniformly bright. The distinct impression was of a diamond ring surrounding the primary disk, with the secondary being the jewel. Amazing!
Show
20/06/15
oldscope
very difficult
separated
do not miss it!
This is a tough but gorgeous double. Hard to find but there is another star near it at almost the same mag.
WDS 21441+2845 STF 2822 AB (Mu1 Cyg) : MEASURES
Records found: 1
WDS 21441+2845 (Mu1 Cyg) : VIRTUAL EYEPIECE
Click on the map to see the double of your interest.
Pass over with the mouse cursor to display the catalog designation.
WDS 21441+2845 (Mu1 Cyg) : ALADIN DSS IMAGE @ 21h 44m 08.57s +28° 44' 33.4"
DSS color
DSS blue
2MASS
AllWISE
GALEX
SDSS9
XMM
PanSTARRS
WDS 21441+2845 STF 2822 AB (Mu1 Cyg) : NEIGHBORHOODS
Click on the map to see the double of your interest.
Pass over with the mouse cursor to display the catalog designation.
Show
name
coord_2000
discov#
comp
pa
sep
dist(')
Show
21441+2845
STF2822
AB
325
1.6
Show
21441+2845
STF2822
AC
292
76.6
Show
21441+2845
STF2822
AD
43
197.0
Show
21441+2845
FYM 25
AF
72
111.5
Show
21441+2845
FYM 25
AG
73
168.1
Show
21441+2845
STF2822
BD
45
196.7
1
Show
21441+2845
ES 521
DE
286
17.5
4
Show
21441+2845
FYM 25
DG
164
89.6
4
Show
21444+2824
KPP3373
242
2.1
21
Show
21461+2855
BRT 58
165
4.4
28
Show
21454+2819
J 3145
112
5.4
29
Show
21452+2914
UC 4550
15
42.5
33
Show
21418+2901
MLB 492
114
7.0
35
Show
21462+2817
MLB 540
AB
256
4.1
37
Show
21462+2817
MLB 540
AC
322
8.7
37
Show
21462+2817
ABH 152
AD
68
41.8
37
Show
21462+2817
ABH 152
AE
96
80.1
37
Show
21416+2911
GRV 493
184
44.7
43
Show
21469+2907
CVR 919
201
23.5
43
Show
21474+2855
AG 420
145
7.5
45
Show
21474+2834
A 300
AB
252
2.3
45
Show
21474+2834
A 300
AC
29
7.5
45
Show
21474+2834
A 300
AD
170
8.4
45
Show
21420+2924
MLB 539
171
4.8
48
Show
21423+2800
GRV 494
323
62.9
51
Show
21439+2751
HO 166
233
0.2
54
Show
21410+2920
STT 448
31
0.1
55
Show
21442+2942
MLB 493
330
8.6
57
Show
21480+2819
MLB 541
340
9.9
58
Show
21470+2930
GRV 503
331
20.4
60
Show
21473+2932
STJ 58
193
1.8
64
Show
21458+2945
DAM 236
143
5.9
65
Show
21455+2948
DAM 237
233
6.3
67
Show
21430+2951
KPP 498
58
3.9
68
Show
21420+2741
RAO 465
Aa,Ab
128
0.3
70
Show
21420+2741
RAO 465
AB
303
2.6
70
Show
21390+2826
ES 520
36
9.3
71
Show
21401+2928
BRT 57
137
5.0
72
Show
21458+2954
TDT3146
359
2.5
73
Show
21420+2951
MLB 720
140
7.2
73
Show
21457+2957
TDT3145
250
2.2
75
Show
21477+2740
CVR 922
225
9.9
80
Show
21435+2725
BKO 631
26
5.9
80
Show
21412+2955
GRV 491
21
31.4
81
Show
21435+2721
OSO 155
DG
304
6.1
82
Show
21435+2721
A 299
DE
95
999.9
82
Show
21435+2721
A 299
DF
26
145.8
82
Show
21453+2722
HO 606
93
18.4
85
Show
21435+2721
A 299
AB
67
1.1
85
Show
21435+2721
A 299
AD
64
374.5
85
Show
21435+2721
A 299
BC
325
0.1
85
WDS 21441+2845 : COMPONENTS
A
B
C
D
E
F
B
pa=309.7°
sep=1.88"
C
pa=294.5°
sep=68.54"
pa=294.1°
sep=66.73"
D
pa=44.8°
sep=197.77"
pa=45.4°
sep=197.94"
pa=61.0°
sep=230.66"
E
pa=40.7°
sep=191.34"
pa=41.2°
sep=191.38"
pa=58.0°
sep=220.43"
pa=288.2°
sep=15.49"
F
pa=69.4°
sep=99.16"
pa=70.4°
sep=100.11"
pa=87.6°
sep=155.33"
pa=203.8°
sep=115.30"
pa=196.1°
sep=114.83"
G
pa=70.3°
sep=149.37"
pa=70.9°
sep=150.33"
pa=83.9°
sep=204.17"
pa=179.2°
sep=90.03"
pa=170.4°
sep=96.20"
pa=72.1°
sep=50.24"
21441+2845 A
Name
Mu1 Cyg
Coord arcsec 2000
214408.57+284433.4
Mag
4.75
Spectral class
F6V (yellow-white)
PmRA
260.00
PmDE
-243.0
SAO
89940
HIP
107310
Tycho2
2201-02078-1
HD
206826
HR
8309
GC
30438
BD
BD+28 4169
Bayer
Mu 1 Cygni
Bayer name
Mu1
Flamsteed
78 Cygni
Flamsteed name
78 Cyg
Tycho2
2201-02078-1
Pflag
P
RAmdeg
326.03572417
DEmdeg
28.74264837
PmRA
277.4
PmDE
-251.1
E RAmdeg
3
E DEmdeg
3
E pmRA
2.7
E pmDE
2.6
EpRAm
1991.91
EpDEm
1992.01
Num
3
Q RAmdeg
1.0
Q DEmdeg
0.3
Q pmRA
1.0
Q pmDE
0.3
BTmag
5.223
E BTmag
0.014
VTmag
4.745
E VTmag
0.009
Prox
20
TYC
T
HIP
107310
CCDM
A
RAdeg
326.03507722
DEdeg
28.74316972
EpRA 1990
1.92
EpDE 1990
2.02
E RAdeg
3.1
E DEdeg
3.3
Posflg
D
Corr
0.3
SAO
89940
DelFlag
RA1950
PmRA1950
0.022
DE1950
PmDE1950
-0.238
Vmag
4.7
SpType
F5
Double code
Source
70
CatNum
30438
DM
BD+28 4169
DMcomp
A
BDsup
HD
206826
M HD
0
GC
30438
RA1950rad
5.68062827
DE1950rad
0.49770008
PmRA2000
0.0222
PmDE2000
-0.241
Catalog
H
HIP
107310
Proxy
H
RAhms
21 44 08.40
DEdms
+28 44 35.6
Vmag
4.49
VarFlag
R Vmag
H
RAdeg
326.035
DEdeg
28.7432
AstroRef
A
Plx
44.64
CCDM
21442+2845
N CCDM
I
Nsys
2
Ncomp
2
MultFlag
C
Source
Qual
A
M HIP
AB
Theta
302
Rho
2.002
HD
206826
BD
BD+28 4169
CD
CP
Dm number
+28 4169
VIred
0.55
SpType
F6V
R SpType
Coord arcsec 2000
214408.40+284435.6
HIP
107310
Sn
15
So
3
Nc
2
RArad
5.6903845519
DErad
0.5016638713
Plx
44.97
PmRA
260.72
PmDE
-243.21
E RArad
0.33
E DErad
0.3
E Plx
0.43
E pmRA
0.36
E pmDE
0.31
Hpmag
4.6029
E Hpmag
0.0004
SHp
0.005
VA
0
BV
0.512
E BV
0.007
VI
0.58
21441+2845 B
Coord arcsec 2000
214408.46+284434.6
Coord calc
214408.46+284434.6
Mag
6.18
Spectral class
G2V (yellow)
PmRA
260.00
PmDE
-243.0
Tycho2
2201-02078-2
Calc delta mag
1.43
Tycho2
2201-02078-2
Pflag
P
RAmdeg
326.03572417
DEmdeg
28.74264837
PmRA
277.4
PmDE
-251.1
E RAmdeg
3
E DEmdeg
3
E pmRA
2.7
E pmDE
2.6
EpRAm
1991.91
EpDEm
1992.01
Num
3
Q RAmdeg
1.0
Q DEmdeg
0.3
Q pmRA
1.0
Q pmDE
0.3
BTmag
6.785
E BTmag
0.014
VTmag
6.179
E VTmag
0.009
Prox
20
TYC
T
HIP
107310
CCDM
B
RAdeg
326.03454639
DEdeg
28.74346778
EpRA 1990
1.92
EpDE 1990
2.00
E RAdeg
3.3
E DEdeg
3.7
Posflg
D
Corr
0.3
21441+2845 C
Coord arcsec 2000
214403.83+284501.8
Mag
12.93
Calc delta mag
8.18
Calc coord
yes
21441+2845 D
Coord arcsec 2000
214419.17+284653.7
Coord calc
214419.17+284653.7
Mag
6.94
Spectral class
A5 (white)
PmRA
-1.00
PmDE
-54.0
SAO
89944
HIP
107326
Tycho2
2201-00786-1
HD
206874
GC
30442
BD
BD+28 4171
Calc delta mag
2.19
Tycho2
2201-00786-1
Pflag
RAmdeg
326.07993096
DEmdeg
28.78160134
PmRA
-1.1
PmDE
-54.5
E RAmdeg
4
E DEmdeg
4
E pmRA
1.1
E pmDE
1.0
EpRAm
1991.64
EpDEm
1991.67
Num
12
Q RAmdeg
0.8
Q DEmdeg
0.8
Q pmRA
0.6
Q pmDE
0.8
BTmag
7.329
E BTmag
0.015
VTmag
6.940
E VTmag
0.010
Prox
999
TYC
T
HIP
107326
CCDM
RAdeg
326.07993361
DEdeg
28.78172278
EpRA 1990
1.93
EpDE 1990
1.98
E RAdeg
3.5
E DEdeg
4.0
Posflg
Corr
0.2
SAO
89944
DelFlag
RA1950
PmRA1950
-0.0006
DE1950
PmDE1950
-0.048
Vmag
6.9
SpType
A5
Double code
Source
70
CatNum
30442
DM
BD+28 4171
DMcomp
BDsup
HD
206874
M HD
0
GC
30442
RA1950rad
5.68147705
DE1950rad
0.49832916
PmRA2000
-0.0005
PmDE2000
-0.052
Catalog
H
HIP
107326
Proxy
RAhms
21 44 19.18
DEdms
+28 46 54.2
Vmag
6.89
VarFlag
R Vmag
H
RAdeg
326.08
DEdeg
28.7817
AstroRef
Plx
12.99
CCDM
21442+2845
N CCDM
I
Nsys
2
Ncomp
1
MultFlag
Source
Qual
M HIP
Theta
Rho
HD
206874
BD
BD+28 4171
CD
CP
Dm number
+28 4171
VIred
0.48
SpType
A5
R SpType
Coord arcsec 2000
214419.18+284654.2
HIP
107326
Sn
5
So
0
Nc
1
RArad
5.6911684504
DErad
0.5023360234
Plx
11.6
PmRA
-0.7
PmDE
-53.92
E RArad
0.44
E DErad
0.45
E Plx
0.63
E pmRA
0.53
E pmDE
0.54
Hpmag
6.9882
E Hpmag
0.0011
SHp
0.008
VA
0
BV
0.411
E BV
0.015
VI
0.48
21441+2845 E
Coord arcsec 2000
214418.05+284658.5
Mag
13.13
Calc delta mag
8.38
Calc coord
yes
21441+2845 F
Coord arcsec 2000
214415.63+284508.2
Mag
12.64
PmRA
6.00
PmDE
6.0
Calc delta mag
7.89
Calc coord
yes
21441+2845 G
Coord arcsec 2000
214419.27+284523.7
Mag
13.77
PmRA
4.00
PmDE
2.0
Calc delta mag
9.02
Calc coord
yes