Tau Piscis Austrini — Double Star in Piscis Austrinus
Observe
1Physical Properties
Magnitude
4.92
Spectral Type
F6V
Star Color
Yellow
(B-V 0.48)
Distance
62 ly
2Position & Identifiers
RA
22h 10m 08.8s
Dec
-32° 32' 54.0"
Constellation
Piscis Austrinus
(PsA)
HR
8447
HIP
109422
HD
210302
SAO
213602
Bayer
Tau
Flamsteed
15 PsA
Querying VizieR catalog...
3How easy to split?
Primary
4.9 mag
Companion
11.4 mag
Separation
1.4″
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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
To reach "Medium" at Bortle 3, you'd need at least a 970 mm reflector.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Jul – Sep
(peak: Aug)
5Multiple Star System
Separation
1.4″
Companion Mag
11.4
Star Colors
A: Yellow
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 4.9 · B: 11.4 · Sep: 1.4″ · PA: ? · N up, E right
Unresolved · 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
14
Light Travel Time Machine
15
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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