About image
Messier 61 belongs to the Virgo Cluster and lies at a distance of 50 million light years.
Its angular size of 6.5’x8.5’ corresponds to a maximum disc diameter of 95000 light years.
The galaxy shows itself with an inclination of 25°, allowing to view the spiral pattern: this is dominated by two arms which join onto a bar structure in the inner region.
Several HII regions are visible on the arms.
[Text adapted from “The Cambridge Photographic Atlas of Galaxies”]
Two others bright galaxies are visible in the image: NGC 4301 (in the top right side) and NGC 4292 (in the bottom right side).
Several other remote galaxies are visibile in the background.
Technical data
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 47x300" bin3 -15C
R 16x300" bin3 -15C
G 16x300" bin3 -15C
B 16x300" bin3 -15C
all gain 100
Total integration 7h55'
Acquisition Voyager, PHD2
Processing Pixinsight 1.8,
Photoshop CS5, StarXTerminator, NoiseXTerminator, BlurXTerminator
SQM-L 21.18
Location Promiod (Aosta
Valley, Italy), own remote observatory
Date 19 April 2023, 18 February / 11 April 2024