DN Geminorum

It was discovered by Norwegian variable star observer Sigurd Einbu[3] on March 12, 1912 before reaching peak brightness, which allowed early-stage spectra to be collected by Yerkes Observatory.

[5] The nova reached a maximum brightness of around 3.5 mag before declining,[6] which means it was visible to the naked eye.

Its brightness decreased over the following 36 days by 3 magnitudes as it gradually faded from sight.

The light curve saw two maxima a few months after the outburst, along with strong oscillations.

[2] The system is located approximately 4,500 light years from the Sun based on parallax, with its visual magnitude being diminished by an extinction of 0.53±0.12 due to interstellar dust.

The light curve of DN Geminorum, plotted from AAVSO data