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RS Ophiuchi — Variable Star in Ophiuchus

Observable Variable Star Showpiece (78/100)

Range: 4.3 - 12.5, Period: 453.6d, Type: NR+LB

Magnitude 4.3–12.5m VariableStar Ophiuchus (Oph) Visible
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1Physical Properties

Magnitude 4.30
Range 4.3 - 12.5
Period 454 days
Variable Type Recurrent Nova
Spectral Type Peculiar

2Position & Identifiers

RA 17h 50m 13.0s
Dec -06° 42' 28.0"
Constellation Ophiuchus (Oph)
HR 9129
Variable ID RS Oph

3How easy to follow?

Magnitude 4.3 – 12.5 mag Amplitude 8.2 mag Period 453.6 d Type NR+LB
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Equipment Bortle 3 Bortle 4 Bortle 5
Naked eye Imp. Imp. Imp.
50mm finder Imp. Imp. Imp.
150mm scope Hard+ 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 180 mm reflector.

4Visibility

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Best season May – Jul (peak: Jun)

5Survey Image

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6Light Curve

7Comparison Stars

Nearby stable stars for estimating brightness (AAVSO)

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9

Compare Stars

10

Spectral Classification

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

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15Stellar Notes

Recurrent Nova; Recurrent nova; Last eruption 2021

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.

Y Oph
Medium
Pulsating variable, period 17.1d
Variable Star mag 6.21 0.8° Ophiuchus
Tau Oph
HIP 88404; Tau Ophiuchi; 69 Ophiuchi
Hard+
Tight double — a rewarding split at 1.4″
Double Star mag 5.24 3.5° Ophiuchus
NGC 6517
Medium+
Globular cluster — dense ball of ancient stars
Globular Cluster mag 10.3 3.7° Ophiuchus
Collinder 350
Easy
Open cluster
Open Cluster mag 6.1 8.0° Ophiuchus
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