Iota Serpentis — Double Star in Serpens
Observe
1Physical Properties
Magnitude
4.52
Spectral Type
A1V
Star Color
White
(B-V 0.04)
Distance
297 ly
2Position & Identifiers
RA
15h 41m 33.1s
Dec
+19° 40' 13.0"
Constellation
Serpens
(Ser)
HR
5842
HIP
76852
HD
140159
SAO
101682
Bayer
Iota
Flamsteed
21 Ser
Double Cat
9744
Querying VizieR catalog...
3How easy to spot?
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| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Medium+ | Medium | Medium |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
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)
5Multiple Star System Quadruple
Components
4 (quadruple)
Component IDs
AB
Separation
0.2″
Companion Mag
5.2
Companion Sp
A1V
Position Angle
64°
Star Colors
A: White
B: White
Discoverer
HU 580
AB 5.2 A1V, 5.3 AIV, 11.07y, a = 0.117". AB combined mag., color. Resolved by speckle interferometry 1986.45, | sep. 0.05".
Separation over time
Period: 21.9 y
Eccentricity: 0.094
Now: 0.17", PA 73°
-0.06" in 5 years
Apparent separation over time, computed from ORB6 orbital elements. Steep curves indicate fast-changing pairs — catch them while they're splittable.
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
Pleiades group.
0.012" to 0.026".
15
Light Travel Time Machine
16
Relativistic Travel
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.
Gudja
HIP 77450; Kappa Serpentis; 35 Serpentis
Cool red giant
Star
mag 4.09
2.3°
Serpens
NGC 5962
Bright spiral galaxy
Galaxy
mag 11.4
3.3°
Serpens
Marsic
Kappa Her (BS6008)
Easy double, sep 27.1″
Double Star
mag 5.00
6.8°
Hercules
Blaze Star
HR 5958
Mira-type variable, range 2.0–10.8
Variable Star
mag 10.00
7.5°
Corona Borealis
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