Zeta Crateris — Double Star in Crater
Observe
1Physical Properties
Magnitude
4.73
Spectral Type
G8IIIa
bright giant
Star Color
Orange
(B-V 0.97)
Distance
109 ly
2Position & Identifiers
RA
11h 44m 45.8s
Dec
-18° 21' 03.0"
Constellation
Crater
(Crt)
HR
4514
HIP
57283
HD
102070
SAO
156869
Bayer
Zeta
Flamsteed
27 Crt
Querying VizieR catalog...
3How easy to split?
Primary
4.7 mag
Companion
7.8 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
To reach "Medium" at Bortle 3, you'd need at least a 870 mm reflector.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Feb – Apr
(peak: Mar)
5Multiple Star System
Separation
0.4″
Companion Mag
7.8
Position Angle
102°
Star Colors
A: Orange
Discoverer
HDS1658
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 4.7 · B: 7.8 · Sep: 0.4″ · PA: 102° · N up, E right
Unresolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″
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
Sirius group? UMa stream.
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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