Andromeda and TRIANGULUM With a Portrait Lens

When it comes to imaging galaxies it's natural to think that a large telescope is required, we picture of Hubble orbiting in space or giant domes on Hawaii or in the Chilean desert. And for the majority this is true due to the vast distances involved. However, there are a handful both large and close enough that they can be imaged with a small camera lens. Conveniently the two with the largest apparent size, that are visible from the northern hemisphere, are close enough in the sky that they can be imaged together.

Shown above are the Andromeda and Triangulum galaxies, our two nearest large neighbours. Andromeda is slightly larger than our own Milky Way and is thought to contain a trillion stars, while Triangulum has a relatively modest 40 billion. The bright star in the middle is Mirach, a red giant roughly a hundred times larger than out Sun. While they are relatively faint objects - the core of Andromeda can see seen through moderate light pollution while Triangulum is only visible from the darkest sites - they occupy considerable real-estate in the sky. Here's the Moon pasted in to give a sense of scale.

The image above was taken with a cheap 50mm lens at f4.5, using an entry-level DSLR camera and a simple tracking mount as shown below. It's about an hours worth of 210 seconds exposures, combined in Deep Sky Stacker and then processed in my usual erratic manner.

For a closer look at Andromeda I used a 200mm lens to take the image below, quadrupling the magnification. The image below has also been cropped for an even closer view.

The yellow core indicates a population of older stars while the bluer spiral arms are a sign of recent star formation. There are two other small galaxies in this image, M32 and M110, both satellites of Andromeda. Our own galaxy also has two prominent satellites, the Magellanic Clouds, that are visible from the Southern Hemisphere. The larger of the two has an apparent size of almost 11 by 9 degrees, twenty times the width of the full Moon. Hopefully someday I'll get a chance to image them on a trip south of the equator.

Finally, here's a wide angle shot taken with a kit lens, showing Andromeda Triangulum relative to the Milky Way. The W-shaped constellation of Cassiopeia is in the centre of the frame but it's quite difficult to spot against the dense starfield.