Regulus & Leo I Dwarf Galaxy (Markus Horn)

Regulus & Leo I Dwarf Galaxy

One of the brightest stars in the night sky and a dwarf galaxy right next to it: Regulus and the dwarf galaxy Leo I are a fascinating pair that I've had on my to-do list for quite some time.

However, my first attempt failed, because, after stacking, it turned out that a spike from Regulus was going right through the Leo I galaxy. I hadn't considered the spikes at all during the preparation of the capture. Fortunately, a new opportunity arose four weeks later, and I rotated the tube of my Newtonian telescope so that Leo I was now located between the spikes. In the final stack, Leo I was nicely clear, bright, and clearly visible, so I could keep the editing very simple. Thanks to the CNC machined secondary spider, Regulus' spikes were also nearly perfect and required no corrections at all. The Nexus reducer took the f/5 1000mm Newton down to 750mm f/3.75 and did a great job! I wish every image would work out like this...I hope you enjoy my version of this odd couple!

Here are some more facts:
Regulus is not really a single star, but a multiple star system. It consists of two pairs of stars. Regulus A, the primary component in the Regulus system, is a spectroscopic binary star composed of a blue-white main sequence star with the spectral classification B7 V and a companion believed to be a white dwarf. With a visual magnitude of 1.35, Regulus A is reponsible for the star system’s brightness and bluish colour. The system lies approximately 79 light years from the Sun.Leo I is a dwarf spheroidal galaxy in the constellation Leo. At about 820,000 light-years distant, it is a member of the Local Group of galaxies and is thought to be one of the most distant satellites of the Milky Way galaxy.Leo I is located only 12 arc minutes from Regulus. For that reason, the galaxy is sometimes called the „Regulus Dwarf“. Scattered light from the star makes studying the galaxy more difficult, and it was not until the 1990s that it was detected visually. Typical to a dwarf galaxy, the metallicity of Leo I is very low, only one percent that of the Sun. The galaxy may be embedded in a cloud of ionized gas with a mass similar to that of the whole galaxy.

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Status	Advanced success
Started	...
Astrometry.net job	9684822
PixInsight job	BUQD2O0CFB64AQ5Q2JALMF9QO27M3QUD
PixInsight queue size	n/a
PixInsight stage	TASK_LOG

RA (center)	10h08m25s.22
RA (top/left)	10h04m50s.100
RA (top/right)	10h11m14s.94
RA (bottom/right)	10h12m00s.20
RA (bottom/left)	10h05m34s.97

Dec (center)	+12°00′25″.5
Dec (top/left)	+11°37′52″.10
Dec (top/right)	+11°21′11″.1
Dec (bottom/right)	+12°22′46″.8
Dec (bottom/left)	+12°39′29″.8

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