Tau Serpentis — Double Star in Serpens
HIP 76878; Tau7 Serpentis; 22 Serpentis
Observe
1Physical Properties
Magnitude
5.81
Spectral Type
A2m
Star Color
White
(B-V 0.20)
Distance
155 ly
2Position & Identifiers
RA
15h 41m 54.7s
Dec
+18° 27' 50.0"
Constellation
Serpens
(Ser)
HR
5845
HIP
76878
HD
140232
SAO
101686
Bayer
Tau7
Flamsteed
22 Ser
Querying VizieR catalog...
3How easy to split?
Primary
5.8 mag
Companion
10.4 mag
Separation
2.4″
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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. | 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 270 mm reflector.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Apr – Jun
(peak: May)
5Multiple Star System
Separation
2.4″
Companion Mag
10.4
Position Angle
88°
Star Colors
A: White
B: Orange
Discoverer
DRS 17
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 5.8 · B: 10.4 · Sep: 2.4″ · PA: 88° · N up, E right
Resolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″
Explore
6
Size Comparison
Querying VizieR for stellar data…
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
Hyades group.
Also classified A8Vams.
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.
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