HIP 99457 — Double Star in Capricornus
Observe
1Physical Properties
Magnitude
6.49
Range
6.16 - 6.49
Variable Type
Gamma Cassiopeiae (Eruptive Be Star)
Spectral Type
B1V
Star Color
Blue
(B-V -0.15)
2Position & Identifiers
RA
20h 11m 10.1s
Dec
-08° 50' 32.0"
Constellation
Capricornus
(Cap)
HR
7709
HIP
99457
HD
191639
SAO
144144
Variable ID
Var
Querying VizieR catalog...
3How easy to split?
Primary
6.5 mag
Companion
11.8 mag
Separation
3.5″
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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 | Hard+ | Hard+ | Hard+ |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
To reach "Medium" at Bortle 3, you'd need at least a 250 mm reflector.
4Visibility
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Best season
Jun – Aug
(peak: Jul)
5Multiple Star System
Separation
3.5″
Companion Mag
11.8
Position Angle
150°
Star Colors
A: Blue
Discoverer
OUD 8
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 6.5 · B: 11.8 · Sep: 3.5″ · PA: 150° · N up, E right
Resolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″
Explore
6
Size Comparison
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7
Compare Stars
8
Spectral Classification
9
Hertzsprung-Russell Diagram
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10
Stellar Lifecycle
11
Blackbody Spectrum
12
Stellar Absorption Spectrum
Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.
13
Stellar Fusion
Discover
14Stellar Notes
Amp. 0.3V, 0.09U, 16.82d. Magnetic var.
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.
V1401 Aql
Semi-regular variable, range 6.2–6.5
Variable Star
mag 6.34
3.1°
Aquila
57 Aql
Easy double, sep 36.3″
Double Star
mag 5.71
4.1°
Aquila
NGC 6835
Edge-on galaxy
Galaxy
mag 12.5
5.5°
Sagittarius
Dabih
HIP 100345; Beta Capricorni; 9 Capricorni
Colorful double, sep 205.2″
Double Star
mag 3.08
6.4°
Capricornus
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