Something to image in the strong moonlight. Mizar (Zeta Ursae Majoris) has 2 partners: the brighter one you can see is 14 arcsecs away at mag 4 but there’s also one at 0.04 arcsecs separation and mag. 2 that we can’t see separately. Alcor is a binary too with an 8th magnitude red dwarf companion, 1 arcsec away from the primary.
So – because there’s no night in Scotland from May to August, I went south to the Languedoc hills. Sainte-Polycarpe in the Aude region to be precise. First real use of my Skywatcher Star Adventurer mount. Great fun, still a lot to learn, but got some decent images. Also made a fun little video story of my holiday in a beautiful region of France.
DIY wide angle mount using old ETX90EC mount. Horrible vignetting caused by IDAS filter in front of lens, but could be removed with flats. Proves the drive works though. Using an old fixed 135mm film lens (approx. 80mm equivalent).
2017-02-01 18:50UT Canon EOS 600D, ISO 1600 5 x 25s, auto darks 135mm film lens – very cheap and old 2″ IDAS P2 LPR filter in front of lens Processed in Nebulosity, PhotoShop and Lightroom.
Mag 6+? 2013-08-30 21:28 UT 200mm f5 newtonian, unguided 4×30s ISO 800, darks Canon EOS 350D modded, Astronomik CLS Captured in APT, Processed in Nebulosity, PS CS5
Discovered 14 Aug 2013 by Koichi Itagaki of Yamagata, peaked at mag. 4.5. It’s about 13,000 light years away. Was originally quite blue but is now much redder – this is what sometimes happens as novae evolve.
The nova was discovered by Koichi Itagaki of Yamagata, Japan, in an image taken at 14hhUniversal Time (2 p.m. EDT) on August 14th. It was not present in a photo that he took the previous day. Here is the announcement from the IAU’s Central Bureau for Astronomical Telegrams. The star was apparently 17th magnitude before erupting, so it brightened roughly 100,000-fold to its peak on August 16th.
A classical nova happens in a special kind of tightly-orbiting binary star system: one where a relatively normal star pours a stream of hydrogen onto the surface of a companion white dwarf. When the layer of fresh hydrogen on the white dwarf’s surface grows thick and dense enough, the bottom of the layer explodes in a runaway hydrogen-fusion reaction — a hydrogen bomb in the shape of a thin shell roughly the size of Earth. The underlying white dwarf remains intact, and as new hydrogen builds up, the process may repeat in a few years to tens of thousands of years.