The Triangulum Galaxy (also known as M33) is the third-largest galaxy in the Local Group, after the Andromeda Galaxy (M31) and our very own Milky Way. It’s 2.73 million light-years from Earth, and contains around 40 billion stars.
Askar 130PHQ: November 2024
This was a fairly straight-forward imaging project, for once! Most galaxies are so far away that they appear as little more than tiny dots in the sky, but this particular one is a relatively close-by neighbour. This means that it’s large enough in the sky that my Askar 130PHQ‘s focal length of 1000mm is well-suited for framing.
The Triangulum Galaxy is a broadband target, so I just used an Optolong L-Quad Enhance filter to help with light pollution. I find that particular filter also brings out red hydrogen-alpha regions, of which there are quite a few in the galaxy’s spiral arms. I boosted the saturation of the red a little more during processing, to help those areas pop.
The most prominent of those red areas is called NGC 604 (highlighted in the image below). This is a stellar nursery; like the Triangulum Galaxy’s version of our own Orion Nebula, but about 40 times bigger!
WBPP stats
Imaging details
* 11 – 22 November2024
* Bristol, UK (Bortle 8)
* Telescope: Askar 130PHQ Flatfield Astrograph
* Camera: ZWO ASI 2600MC-PRO
* Mount: Sky-Watcher EQ6-R PRO
* Guide: William Optics 50mm Guidescope with 1.25″ RotoLock; ZWO ASI 120MM Mini
* Control: ASIAIR Plus
* Software: PixInsight, Lightroom
* Filters:
– Optolong L-Quad Enhance (RGB): 216 x 5 minutes (18 hours)
Total exposure time: 18 hours
By Lee Pullen
Processing walkthrough
Example source data
Seestar S50
Here’s a photo of this target taken from the same Bortle 8 city location as the main image, but using a Seestar S50 smart telescope. The exposure time was 78 minutes. The shape of the galaxy, including its spiral arms, can be seen.
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