Eta Serpentis — Star in Serpens
About Eta Ser
Description
Eta Serpentis is an orange giant of spectral type K0III-IV at magnitude 3.26 in Serpens Cauda. Located about 62 light-years from Earth, it has a luminosity of roughly 24 times solar. It lies in the tail part of Serpens, east of Ophiuchus.
Observing Tips
Eta Ser lies in Serpens Cauda (the serpent's tail), east of Ophiuchus. It is a warm orange star in the summer sky. The Eagle Nebula (M16) and the Omega Nebula (M17) lie in the same general region. Best observed June through September.
History
Eta Serpentis has no widely used traditional name. Serpens is the only constellation divided into two parts — the head (Caput) and tail (Cauda) — separated by Ophiuchus the Serpent Bearer.
Fun Facts
Eta Ser's location in Serpens Cauda places it near some of the most famous deep-sky objects in the summer sky, including the Eagle Nebula with its iconic 'Pillars of Creation' and the bright Omega Nebula.
Observe
1Physical Properties
2Position & Identifiers
3How easy to spot?
| Equipment | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| Naked eye Naked eye | Easy | Easy | Medium+ |
| 50 mm finder 50mm finder | Easy | Easy | Easy |
| 150 mm telescope 150mm scope | Easy | Easy | Easy |
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
5Survey Image
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Explore
7
Size Comparison
8
Compare Stars
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Spectral Classification
10
Hertzsprung-Russell Diagram
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
15Stellar Notes
16
Light Travel Time Machine
17
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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