Eta Telescopii — Double Star in Telescopium
Observe
1Physical Properties
Magnitude
5.05
Spectral Type
A0Vn
Star Color
Blue-white
(B-V 0.02)
Distance
163 ly
2Position & Identifiers
RA
19h 22m 51.1s
Dec
-54° 25' 25.0"
Constellation
Telescopium
(Tel)
HR
7329
HIP
95261
HD
181296
SAO
246055
Bayer
Eta
Querying VizieR catalog...
3How easy to split?
Primary
5.1 mag
Companion
11.9 mag
Separation
4.2″
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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 380 mm reflector.
4Visibility
Set a location in User Settings to see visibility data.
Best season
Jun – Aug
(peak: Jul)
5Multiple Star System
Separation
4.2″
Companion Mag
11.9
Companion Sp
M7.5
Position Angle
167°
Star Colors
A: Blue-white
B: Red
Discoverer
LWR 3
Eyepiece View
80x
Dawes: 1.9″
TFOV: 0.6°
Realistic = true angular size
A: 5.0 · B: 11.9 · Sep: 4.2″ · PA: 167° · 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
14
Light Travel Time Machine
15
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.
IC 4837
Barred spiral galaxy
Galaxy
mag 12.0
1.1°
Telescopium
NGC 6752
Large bright globular cluster
Globular Cluster
mag 5.4
5.8°
Pavo
NU Pav
Semi-regular variable, range 4.9–5.3
Variable Star
mag 5.13
7.2°
Pavo
Arkab Prior
HIP 95241; Beta1 Sagittarii
Easy double, sep 28.3″
Double Star
mag 4.01
10.0°
Sagittarius
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