Overview
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.
Background
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.
Science
The most prominent red area 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!
Imaging details
| Date | 11 – 22 November2024 |
| Location | 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 |
| Image credit | Lee Pullen |
Processing
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.
See below for a full video walkthrough of how I processed the image.
Source data
Seestar S50
Here’s an image of the Triangulum Galaxy taken from my city centre location using a ZWO Seestar S50 smart telescope.
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