Nova Delphinus 2013 (Nova Del 2013) - Dimming

This classical nova is getting dimmer. It has diminished to magnitude 6 - 6.5, one month after my first image was taken. Notice that the star has turned to a reddish color. The energy from the nova is being absorbed by the surrounding material and is being re-emitted in the Hydrogen-alpha wavelength. This energy is also being spread out over a larger area and it is causing a temperature drop. The materials that were blasted out are starting to condense and the light is getting absorbed by that material. Scattering of the starlight is producing a red color.

15 images x 180-second subframes, Total= 45 minutes. Takahashi Epsilon-180, f/2.8 hyperbolic astrograph, Unmodified Canon 20D DSLR, Astronomik CLS Light Pollution filter, ISO 800, Losmandy Gemini G-11 EQ mount. Acquisition, calibration, alignment, combine and digital development processing by Images Plus 3.82b, Additional processing using Adobe Photoshop. ATMoB Clubhouse, Westford, MA, 8 September 2013.