Tau Arietis — Double Star in Aries
HIP 15627; Tau1 Arietis; 61 Arietis
Observe
1Physical Properties
Magnitude
5.28
Spectral Type
B5IV
subgiant
Star Color
Blue-white
(B-V -0.07)
2Position & Identifiers
RA
03h 21m 13.6s
Dec
+21° 08' 49.0"
Constellation
Aries
(Ari)
HR
1005
HIP
15627
HD
20756
SAO
75886
Bayer
Tau1
Flamsteed
61 Ari
Querying VizieR catalog...
3How easy to split?
Primary
5.3 mag
Companion
8.1 mag
Separation
0.9″
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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 | 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 340 mm reflector.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Oct – Dec
(peak: Nov)
5Multiple Star System Triple
Components
3 (triple)
Component IDs
O
Separation
0.9″
Companion Mag
8.1
Position Angle
217°
Star Colors
A: Blue-white
B: Yellow-white
Discoverer
COU 259
Suspected of being double or triple by Tebbutt in 1893. Components 5.4, 7.9v, sep. 0.15", and 8.4v at 0.67".
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 5.3 · B: 8.1 · Sep: 0.9″ · PA: 217° · 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
14Stellar Notes
Cas-Tau OB1.
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.
Epsilon Ari
HIP 13914; Epsilon Arietis; 48 Arietis
Tight double — a rewarding split at 1.3″
Double Star
mag 4.63
5.1°
Aries
NGC 1156
Galaxy
Galaxy
mag 11.7
6.4°
Aries
Rho Ari
HIP 13654; Rho2 Arietis; 45 Arietis
Semi-regular variable, range 5.6–6.0
Variable Star
mag 5.91
6.6°
Aries
Asterope
HIP 17579; 21 Tauri
Easy double, sep 149.6″
Double Star
mag 5.76
6.6°
Taurus
M45
Pleiades, Seven Sisters or Subaru
Open cluster
Open Cluster
mag 1.6
6.7°
Taurus
Alcyone
HIP 17702; Eta Tauri; 25 Tauri
Easy double, sep 117.6″
Double Star
mag 2.87
6.7°
Taurus
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