Iota Ophiuchi — Double Star in Ophiuchus
Observe
1Physical Properties
Magnitude
4.38
Spectral Type
B8V
Star Color
Blue-white
(B-V -0.08)
Distance
112 ly
2Position & Identifiers
RA
16h 54m 00.5s
Dec
+10° 09' 55.0"
Constellation
Ophiuchus
(Oph)
HR
6281
HIP
82673
HD
152614
SAO
102458
Bayer
Iota
Flamsteed
25 Oph
Querying VizieR catalog...
3How easy to split?
Primary
4.4 mag
Companion
8.7 mag
Separation
0.4″
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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. | V. hard | V. hard | V. hard |
| Celestron C8 (203 mm SCT) C8 203mm | V. hard | V. hard | V. hard |
Easy
Medium
Hard
Very hard
Impossible
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
Out of reach for typical amateur telescopes, even at Bortle 3.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Apr – Jun
(peak: May)
5Multiple Star System
Separation
0.4″
Companion Mag
8.7
Position Angle
76°
Star Colors
A: Blue-white
B: Yellow
Discoverer
DCH 120
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 4.4 · B: 8.7 · Sep: 0.4″ · PA: 76° · N up, E right
Unresolved · 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
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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
15
Light Travel Time Machine
16
Relativistic Travel
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Other targets within a few degrees — pan your scope a little and keep exploring.
Visibility scores assume a 150 mm Newton at Bortle 4.
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