.jpg)
What later became known as the Whirlpool Galaxy was discovered on October 13, 1773, by Charles Messier while hunting for objects that could confuse comet hunters, and was designated in Messier’s catalogue as M51. William Parsons, 3rd Earl of Rosse, employing a 72-inch (1.8 m) reflecting telescope at Birr Castle, Ireland, found that the Whirlpool possessed a spiral structure, the first “nebula” to be known to have one. These “spiral nebulae” were not recognized as galaxies until Edwin Hubble was able to observe Cepheid variables in some of these spiral nebulae, which provided evidence that they were so far away that they must be entirely separate galaxies.
The Whirlpool Galaxy, also known as Messier 51a or NGC 5194, is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus. It lies in the constellation Canes Venatici. It is 7.22 megaparsecs (23.5 million light-years) away and 23.58 kiloparsecs (76,900 ly) in diameter.
Imaging telescope: Takahashi FSQ130ED
Imaging camera: ASI 2600MM
Mount: JTW Trident P75
Guiding telescope: Takahashi FS60CB
Guiding camera: QHY 5 II
Focal Extender / Reducer: None
Software: Sequence Generator Pro SGP (for capture) PHD 2 (guiding), Astro Pixel Processor, PixInsight.
Filters: Astrodon LRG&B & Astrodon Ha (3nm)
Accessories: Robofocus Focuser controlled by Lunatico Armadillo, ATIK EFW 3, RB Focus Gaius, RB Focus Excalibur.
Dates: 10th. – 11th Apr. 2024
Frames:
Astrodon Blue 15×120″(30′)
Astrodon Blue 60×60″(1h)
Astrodon Green 15×120″(30′)
Astrodon Green 60×60″(1h)
Astrodon Lum 60×60″(1h)
Astrodon Red 15×120″(30′)
Astrodon Red 60×60″(1h)
Astrodon Ha 30×120″(1h)
Total integration = 6 Hour 30 minutes