Questo è il residuo della supernova noto come Nebulosa Spaghetti, ma più formalmente come Simeis 147 o Sharpless 2-240. E' stato scoperto all'Astr di Crimea
6710 x 4460 px | 56,8 x 37,8 cm | 22,4 x 14,9 inches | 300dpi
Data acquisizione:
13 dicembre 2023
Altre informazioni:
This is the supernova remnant known as the Spaghetti Nebula, but more formally as Simeis 147 or Sharpless 2-240. It was discovered at the Crimean Astrophysical Observatory in 1952, an observatory also known by its name of Simeiz for the location where one of its facilities was located, thus the name of the catalogue of objects that includes entry #147. The supernova that created this nebula exploded some 40, 000 years ago and is about 3, 000 light years away. In the sky it stretches across more than 3°, so it is big! The field of view here is 6.6° by 4.4°. The bright star at right is Elnath in Taurus or Auriga. The nebula itself is in Taurus. This is a stack of 34 x 8-minute exposures through an IDAS NBZ dual-band nebula filter (which passes just green Oxygen III and red Hydrogen-alpha wavelengths) with the filter-modified (by Astrogear) Canon R at ISO1600, blended with a stack of 14 x 4-minute exposures at ISO 800 with no filter. So a total of 5.5 hours of exposure, on December 12, 2023. The nebulosity comes from just the filtered set, while the stars come from the unfiltered set, which recorded nothing at all of the nebulosity but captured the stars' natural colours. However, despite the object having a fair amount of cyan-green OIII emission, and the filter passing it, not a lot got recorded here. There was some light haze in the sky which might have suppressed the shorter wavelengths. But the H-a showed up well. All exposures were with the little Borg 77mm f/4 astrograph, one of the older scopes in my collection (and no longer made) and seldom used in recent years, but its fast speed and field of view were perfect for this target. Autoguided and inter-frame dithered (for eliminating thermal noise specks) with the Lacerta MGEN3 autoguider, on the Astro-Physics Mach1 mount. Nebulosity brought out in Photoshop processing on a starless layer created with RC-Astro Star XTerminator, and using luminosity masks created with Lumenzia, and with applications of t
