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39 Sagittarii — Star in Sagittarius

Magnitude 3.8m Star Sagittarius (Sgr) Visible
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1Physical Properties

Magnitude 3.77
Spectral Type G9IIIb bright giant
Star Color Orange (B-V 1.01)
Distance 142 ly

2Position & Identifiers

RA 19h 04m 41.0s
Dec -21° 44' 30.0"
Constellation Sagittarius (Sgr)
HR 7217
HIP 93683
HD 177241
SAO 187643
Flamsteed 39 Sgr
Double Cat 11996
SIMBAD

3How easy to spot?

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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Easy Medium+ Medium+
50mm finder Easy Easy Easy
150mm scope Easy Easy Easy
Easy Medium Hard Very hard Impossible

Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs

4Visibility

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Best season Jun – Aug (peak: Jul)

5Survey Image

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7

Size Comparison

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8

Compare Stars

9

Spectral Classification

10

Hertzsprung-Russell Diagram

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Read: The Hertzsprung-Russell Diagram — Reading Stars Like a Map
11

Stellar Lifecycle

12

Blackbody Spectrum

13

Stellar Absorption Spectrum

Simulated absorption spectrum based on spectral type. Hover over lines to identify elements.

14

Stellar Fusion

Discover

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.

NGC 6717
Medium+
Compact globular cluster
Globular Cluster mag 10.35 2.4° Sagittarius
NGC 6716
Easy
Rich open cluster
Open Cluster mag 6.9 3.0° Sagittarius
V3879 Sgr
Medium
Semi-regular variable, range 6.0–6.6
Variable Star mag 6.35 5.7° Sagittarius
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