V918 Scorpii — Double Star in Scorpius
Observe
1Physical Properties
Magnitude
5.47
Range
5.42 - 5.50
Period
9.8 days
Variable Type
Ellipsoidal Variable
Spectral Type
O9Ia
supergiant
Star Color
Yellow-white
(B-V 0.40)
2Position & Identifiers
RA
16h 36m 22.5s
Dec
-42° 51' 32.0"
Constellation
Scorpius
(Sco)
HR
6164
HIP
81305
HD
149404
SAO
226953
Variable ID
V918 Sco
Querying VizieR catalog...
3How easy to split?
Primary
5.5 mag
Companion
11.4 mag
Separation
6.8″
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| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | V. hard+ | V. hard+ | V. hard+ |
| 150 mm Newton 150mm Newt. | Hard+ | Hard+ | Hard+ |
| Celestron C8 (203 mm SCT) C8 203mm | Medium | Medium | Medium |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
Best season
Apr – Jun
(peak: May)
5Light Curve
6Multiple Star System
Separation
6.8″
Companion Mag
11.4
Position Angle
120°
Star Colors
A: Yellow-white
Discoverer
SNA 42
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 5.5 · B: 11.4 · Sep: 6.8″ · PA: 120° · N up, E right
Resolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″
Explore
7
Size Comparison
Querying VizieR for stellar data…
8
Compare Stars
9
Spectral Classification
10
Hertzsprung-Russell Diagram
Loading HR diagram…
11
Stellar Lifecycle
12
Blackbody Spectrum
13
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
14
Stellar Fusion
Discover
15Stellar Notes
9.813d, k1 101k/s, K2 60k/s, V1 -37k/s, V2 -28k/s, m1sin3i 1.6, m2sin3i 2.7, | a1sini 13.7, a2sini 8.1.
Ara OB1a. Listed by Buscombe and Kennedy (M.N.R.A.S. 124, 196, 1962) as among Sco-Cen stars. Buscombe now points out | that it is a nonmember background star.
H alpha emission.
Two available determinations of vsini, 140 and 45k/s.
Nearby in the Sky
Other targets within a few degrees — pan your scope a little and keep exploring.
Visibility scores assume a 150 mm Newton at Bortle 4.
NGC 6192
Open cluster
Open Cluster
mag 9.0
0.9°
Scorpius
V919 Sco
Wolf-Rayet star — rare, hot emission spectrum
Star
mag 6.49
3.1°
Scorpius
V861 Sco
Eclipsing binary, period 7.8d
Variable Star
mag 6.15
4.3°
Scorpius
NGC 6139
Globular cluster — dense ball of ancient stars
Globular Cluster
mag 9.2
4.3°
Scorpius
Epsilon Nor
Easy double, sep 22.9″
Double Star
mag 4.47
5.0°
Norma
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