Delta Serpentis — Double Star in Serpens
HIP 76276; Delta Serpentis; 13 Serpentis
About Delta Ser
Description
Delta Serpentis is a multiple-star system about 155 light-years away in the head of the celestial serpent. The primary is an F-type subgiant of spectral class F0 IV at magnitude 3.80. A close F-type companion orbits at 4 arcseconds separation, visible in moderate telescopes. A third component is present at wider separation.
Observing Tips
Delta Ser forms part of the head of Serpens, near Beta Ser. The 4-arcsecond double splits cleanly in a 3-inch telescope at 100x — a satisfying pair of matching white-yellow stars. The wider third component is a binocular target. Best observed April through September.
History
Delta Serpentis retains its Bayer designation in current IAU catalogs.
Fun Facts
Serpens is the only constellation formally divided into two parts (Serpens Caput, the head, and Serpens Cauda, the tail) — with Ophiuchus holding the snake in between. Delta Ser is one of the bright stars of the head, providing an anchor for this unusual two-piece constellation.
Observe
1Physical Properties
2Position & Identifiers
3How easy to split?
| Telescope | Bortle 3 | Bortle 4 | Bortle 5 |
|---|---|---|---|
| 80 mm refractor 80mm refr. | Medium+ | Medium+ | Medium+ |
| 150 mm Newton 150mm Newt. | Easy | Easy | Easy |
| Celestron C8 (203 mm SCT) C8 203mm | Easy | Easy | Easy |
Bortle 3 = rural · 4 = outer suburbs · 5 = suburbs
4Visibility
Set a location in User Settings to see visibility data.
5Multiple Star System Quadruple
Separation over time
Apparent separation over time, computed from ORB6 orbital elements. Steep curves indicate fast-changing pairs — catch them while they're splittable.
Eyepiece View
A: 3.8 · B: 5.2 · Sep: 4.0″ · PA: 171° · N up, E right
Resolved · Rayleigh: 2.3″ · Dawes: 1.9″ · Eff: 2.3″
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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