NGC 2261, Hubble's Variable Nebula
About image
NGC 2261 (also known as Hubble's Variable Nebula) is a small nebula located in the constellation Monoceros.
The nebula is illuminated by the star R Monocerotis (R Mon), which is visible at one end of the nebula.
NGC 2261 was imaged as Palomar Observatory's Hale Telescope's first light by Edwin Hubble on January 26, 1949, so I suppose this is the reason why it was named so.
From physical point of view, it is located at 2500 light years and it is known for its (small) changes in shape and brightness, visible also with small telescopes over months or also weeks.
One explanation proposed for the variability is that dense clouds of dust near R Mon periodically block the illumination from the star.
Technical data R 50x60" bin3 -15C all gain 100
Optic GSO RC12 Truss - Aperture 304mm, focal lenght 2432mm, f/8
Mount 10Micron GM2000 HPSII
Camera ZWO ASI 2600 MM Pro with filter wheel 7 positions
Filters Astrodon Gen2 E-Serie Tru-Balance 50mm unmounted LRGB
Guiding system ZWO OAG-L with guide camera ASI 174MM
Exposure details L 108x60" bin3 -15C
G 50x60" bin3 -15C
B 50x60" bin3 -15C
Total integration 4h18'
Acquisition Voyager, PHD2
Processing Pixinsight 1.8, Photoshop CS5, StarXTerminator, NoiseXTerminator, BlurXTerminator
SQM-L 21.05
Location Promiod (Aosta Valley, Italy), own remote observatory
Date 3 November, 29 November 2024
© Roberto Marinoni 2019 - All rights reserved