M 1

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Observation place
New Mexico


TelescopePlanewave 431mm – 17″, 1940mm FL, f/4,5 with focal reducer
MountPlanewave Ascension 200HR (FLI)
Imaging cameraMicroline PL6303E (FLI) - regulated at -25o Celsius
Image typeHa (RVsB) (Vs for synghetic green)
ExhibitionHa (10 x 10 'bin 1 × 1), R and B (4 x 3' bin 2 × 2 each)
PretreatmentMaxim DL
TreatmentPhotoshop and PixInsight
Specific treatmentCreate a synthetic green image

Object description

Object typeEmission nebula called "The Crab Nebula"
Visual magnitude8,4
Distance6200 light years
Diameter13 light years
Dimension seen from Earth6 x 4 arc minutes 
In visible light, the Crab Nebula is a large, oval mass of filaments, about 6 arc minutes long and 4 arc minutes wide, surrounding a diffuse central blue region. Recent analysis has shown that the star that exploded as a supernova and which is the origin of the Crab Nebula probably appeared in April or early May 1054, reaching a maximum apparent magnitude between -5 and -3 in July 1054. It was then brighter than all other objects in the night sky except the Moon.  

The filaments are the remnants of the supernova's atmosphere and are made up primarily of ionized helium and hydrogen as well as carbon, oxygen, nitrogen, iron, neon, and sulfur. At the very center of the nebula is a pulsar: a neutron star as massive as the Sun. The Crab pulsar spins around 30 times per second.  
M1 is a nebula very popular with amateur astronomers: with its magnitude of 8,4 and its size of 6 X 4 arc minutes, it is a target of choice for both visual observation and astrophotography.

Visual observation should be made in a sky with low light pollution. The nebula is then visible as a faint spot with 7 × 50 or 10 × 50 binoculars. In telescopes 10 cm (4 inches) and larger in aperture, some details in its shape become apparent. Only under excellent viewing conditions and with telescopes of 40 cm (16 inches) or more aperture, can we possibly see the filaments and fine structures.     

In my picture, we can see the very beautiful red colored filaments that surround the central blue region of the nebula. To bring out these filaments as much as possible, I used an alpha Hydrogen (Ha) filter as a luminance image. For the color image, I chose the RGB filters (red and blue with a synthetic green produced with the red and blue images) in order to bring out the very beautiful natural colors of the nebula.  
Richard Beauregard
Sky Astro - CCD
My impression "We cannot be alone in this gigantic universe"