Recurrent Nova RS Ophiuchus

Outburst 2006


Other amateur spectra of this object:

Christian Buil

Benjamin Mauclaire

Paulo Corelli

Evolution of RS Oph Spectrum


Vmag (AAVSO) 11.8

8th September 21:00 UT

Star Analyser 100 l/mm grating

VC200L SC3 modified webcam

RS Oph has now faded to Vmag 11.8.  A reduction in dispersion was needed to maintain a reasonable signal/noise.

The Ha emission line has faded but is still evident. The Fe X and other coronal lines have disappeared. There appears to have been a shift in the continuum towards the red.


Vmag (AAVSO) 10.1

22 April 01:50 UT

Star Analyser 100 l/mm grating

VC200L SC3 modified webcam

The low ionisation level emission lines (H, He, FeII) have now started to fade relative to the continuum.

The high ionisation level 'coronal lines' are still present with several more lines indentified using this reference from the 1985 outburst.

The 1985 outburst of RS Ophiuchi - Spectroscopic results Anupama, G. C.; Prabhu, T. P. Journal of Astrophysics and Astronomy, vol. 10, Sept. 1989, p. 237-255.

Click on the graph for a comparison between this spectrum and one from the 1985 outburst from this paper.

Vmag (AAVSO) 9.5

21st March 04:10 UT

Star Analyser 100 l/mm grating

VC200L SC3 modified webcam

A tentative identification of the lines has been made based on the following papers from the 1958 and 1985 outbursts.

Coronal lines in the post-maximum spectra of RS OPH 1958 Griffin, R. F.; Thackeray, A. D.
The Observatory, Vol. 78, p. 245-247 (1958)

Coronal lines in the postmaximum spectrum of Nova RS Ophiuchi 1985
Wallerstein, G.; Garnavich, P. M.
Astronomical Society of the Pacific, Publications vol. 98, Sept. 1986, p. 875-880.

Since 4th March, a new line has appeared at 6365A. This is suspected to be the coronal line from Fe X caused by the high temperatures and which appeared at about this time in previous outbursts. It seems to be slightly blue shifted from its rest wavelength of 6374A

Vmag (AAVSO) 8.4

4th March 05:00 UT


Little change in relative intensities of features compared with 28th February

Vmag (AAVSO) 8.0

28th February 04:10 UT


The H alpha line intensity has increased significantly relative to the continuum spectrum. The star now appears red visually compared with straw colour on 18/19th Feb

Vmag (AAVSO) 6.9

19th February 05:00 UT

Star Analyser 100 l/mm grating

VC200L SC3 modified webcam

Conditions were good so the dispersion was increased by increasing the grating/CCD distance.

Spectrum corrected for instrument response. See here for more information

The y scale has been increased for the red spectrum to show the continuum detail

Vmag (AAVSO) 6.6

18th February 05:30 UT

Star Analyser 100 l/mm grating

VC200L SC3 modified webcam

Spectrum calibrated for wavelength and instrument spectral response using Gamma Oph (A0v)

The intense H alpha emission line is clear, plus H beta, gamma, delta. Other emission lines are also visible, including one in the IR at 8450A. The feature at 7600A is due to atmospheric absorption.

The base spectrum is flat with a slight increase towards the IR end of the spectrum up to 8500A.

This wide field image (approximately 7 degrees) was taken using a 29mm SLR lens and the SC3 webcam with IR blocking filter and photographic RGB filters. The red colour of the Nova from the H alpha emission is evident. The reported visual magnitude at the time was +6.6 but this does not include the H alpha emission as the eye is not very sensitive to this wavelength. The Nova would not be visible in this image in its quisecent state.