a. v. ley
Helix_LRGB_2_Ha_HDMR_LHE_USM_MT_SAT_PS1
NGC 7293, the “Helix Nebula,” was captured on 09-04-24 and 10-05-2024 at GNTO using a C11 at f/7, an ASI1600 camera with ASI color filters as well as an ASI 7nm bandpass Hα filter, mounted on a Losmandy G11 mount. A total of 72x 300 second subframes were used. Processing was done in PixInsight and Photoshop CS2.
The Helix is a large planetary nebula located in the constellation Aquarius. It is approximately 700 light years away from earth, close by astronomical standards. It is similar in appearance to the Ring Nebula (M 57), but appears to be much larger. The Ring Nebula subtends an angle of ~ 76 arc seconds and is approximately 2300 light years distant, while the Helix Nebula covers 16.3 arc minutes— more than half the diameter of the full moon—and is about 700 light years away. Trigonometry fans will find the actual diameter of M57 as 0.85 light years and that of the Helix as 3.3 light years. The foregoing are based on diameters listed in Will Tirion’s DeepMap 600. Wikipedia lists a much larger diameter for M57 of 230 arc seconds and 25 arc minutes for the Helix. These larger values are probably more relevant to observations made using the Hubble space telescope.
Helix_LRGB_2_Ha_HDMR_LHE_USM_MT_SAT_PS1
NGC 7293, the “Helix Nebula,” was captured on 09-04-24 and 10-05-2024 at GNTO using a C11 at f/7, an ASI1600 camera with ASI color filters as well as an ASI 7nm bandpass Hα filter, mounted on a Losmandy G11 mount. A total of 72x 300 second subframes were used. Processing was done in PixInsight and Photoshop CS2.
The Helix is a large planetary nebula located in the constellation Aquarius. It is approximately 700 light years away from earth, close by astronomical standards. It is similar in appearance to the Ring Nebula (M 57), but appears to be much larger. The Ring Nebula subtends an angle of ~ 76 arc seconds and is approximately 2300 light years distant, while the Helix Nebula covers 16.3 arc minutes— more than half the diameter of the full moon—and is about 700 light years away. Trigonometry fans will find the actual diameter of M57 as 0.85 light years and that of the Helix as 3.3 light years. The foregoing are based on diameters listed in Will Tirion’s DeepMap 600. Wikipedia lists a much larger diameter for M57 of 230 arc seconds and 25 arc minutes for the Helix. These larger values are probably more relevant to observations made using the Hubble space telescope.