The whole formation lies north of the line joining the Prokyon and Betelgeuse. To the south of this line and closer to Betelgeuse, lies the brighter Rosette Nebula.

   In this photo, the north is to the left and up (almost on the diagonal). Framing is done (as in my other photos) based on aesthetic criteria.

  It belongs to the constellation of the Unicorn, and lies in the spiral of Orion (his position of our milky way), 2,700 light-years from us. It occupies about 3 degrees in our sky.  

   South of this formation (right in the photo) is the Cone Nebula. A dark nebula is inserted in front of the emission nebula (ionized hydrogen region HII) who is located behind it,.  Absorbing the light. The (emission) nebula is illuminated by the star S Mon (S Monocerotis or 15 Monocerotis). Pictured this star is located to the right of the center and is the brighter of all. This star is the brightest of the rest stars from this cluster (NGC 2264).  His size has luminocity from +4.62 to +4.68. He's bumpy variable star, at least 8,000 times than our sun. One factor for this variability, it is believed to be caused by changes in his chromosphere, which in turn caught to stellar winds caused by this young star. The intensity of these winds determines  its short life. It has an 8th magnitude companion star, just 2.9 seconds from this (a double star). It is believed that it consist of up to 8 components.

  The region of NGC 2264 contains hydrogen gas clouds, mixed with small dust grains. The majority of the hydrogen atoms are neutral in electrical charge (one proton in which an electron is added). It is called HI region (as opposed to the HII regions due to ionized hydrogen atoms). The HII regions are close to "hot" stars whose audible ultraviolet radiation emitted. This radiation extracts the electron from the nucleus (stellar process called "ionization"). The free electrons connect again with others nuclei after a short period of time, yielding energy by photon emission (light).

  As a final result of these processes is that bright HII regions are mixed with colder HI regions. Stars are formed in more dense (from matter concentration terms) areas, which are called "cores". The Hubble telescope captures young stars formationin this regions.

  Eventually, all these events, mixing regions of ionized gas and dark nebulae material, attach this interesting image of the Christmas Tree Cluster and Cone Nebula.

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Technical data of the photo :

Ha 26x600s, Red 12x300s, Green 8x300s, Blue 7x300s

Mount  : AP GTO

Camera  : QSI 683, -20 C

Telescope  : Takahashi FSQ 106

Skyros Island and Mani Region, Greece, November 2015

Processed in September 2016