- 4″/101mm Telescope = The two Magellanic Clouds and M33, M81, M82
- 6″/152mm Telescope = Messiers and NGC’s
- 8″/203mm Telescope = Considerable structure and views of the Magellanic Clouds and M31, M33, M51, M66, M82, M83, M101, NGC 253, NGC 2403, NGC 2903
- 12″/ 304mm Telescope = H-II regions and the star like inner cores of brighter spiral galaxies.
- 16″/406mm Telescope = Large numbers of Spiral Galaxies
Telescope Specification to Observe GalaxiesIf you are looking to purchase a telescope for viewing galaxies, there are certain things you should look out for. Below, I run through the different specification and what you will most likely need. All astronomical telescopes, regardless of their size, are designed to do two things: (1) Brighten an image (2) Magnify your views of celestial objects. Refractors, Reflectors, and compound telescopes will do this this in different ways, but the commonality between them are:
ApertureAs mentioned previously in this article, the most important specification to consider for your telescope is your Aperture. This is true regardless of whether it is a Refractor, Reflector or Compound Telescope. The Aperture is word to describe the diameter of the telescopes main, light-gathering lens or mirror (the lens or mirror is called the telescope’s objective.) The bigger the aperture, the sharper and brighter your views will ultimately be.
MagnificationThis is essentially how far you can “zoom in” on an object. It is referenced as a multiple of what you can see greater than with your naked eye. So 50x magnification is (50 times what you see with your naked eye). The larger the Aperture, the more Magnification you will be able to use with the best results. It is possible to increase the magnification on any telescope (to do this you would change the eyepieces). However, if the telescope does not have sufficient Aperture, then high magnification will be ineffective (objects will appear blurred). In terms of application, a telescope with a maximum magnification of 50x (50 times the magnification of your naked eye) before it provides blurry images, will enable you to see minor detail of the brightest star clusters and galaxies. However, if you are looking to observe finer detail, you would be looking for a telescope that can provide clear views at 150x magnification +. If your optical quality and observing conditions are good, it is possible to get 20x to 50x of sharp magnification for every inch of aperture. So, a 4″ telescope can give you a max of 200x magnification, whereas a 6″ telescope works optimally at 300x magnification. This is the maximum, the best views a telescope can provide will be at their lowest power.
Focal LengthOne final thing to consider is the Focal Length. Now different telescopes of the same Aperture will have different Focal Lengths. Generally, the higher the Focal Ratio and the longer the telescopes focal length, the better it will be at high magnification. This will also enable you to use longer-focus eyepieces which are much easier to use.
Telescope Accessories to View GalaxiesWith a telescope there are also some extra components which improve and alter its performance. Here are the ones to consider if you are looking at observing galaxies.
EyepiecesEyepieces are the component that form an image from the light your telescope collects. Eyepieces are essentially small magnifying glasses that help you view an image. It is possible to change eyepieces on telescopes which will help you manipulate the magnification. The majority of telescopes will provide a couple of eyepieces in the box, but you can also buy them separately. Its best to get a set that provides you with a range of different magnifications. There are many different designs, but generally, the more expensive the eyepiece, the greater the quality of the elements it is composed of and ultimately the greater the image it will provide.
FindersAnother accessory to consider for your telescope is a finder; this will help you to identify and observe objects in the sky like Galaxies far more easily and effectively. This is because even at its lowest power, a telescope (and any eyepiece) is going to show you a very small section of the sky. Its therefore impossible to really know where you are aiming. A finder therefore helps to overcome this issue. There are different types available starting with a basic “peep sight” ranging to “reflex” sights that utilize red dots and circles to help you mark objects in the sky. The better telescopes will have a finderscope included, but you can also purchase them separately if you wanted to upgrade.
Final Words and ConclusionObserving galaxies is one of the best and most fascinating observations for an Astronomer. In summary, if you want to observe galaxies, always consider which ones, in what level of detail, and then think about your budget and preferences. The greater the Aperture of the telescope the more you will ultimately be able to see – but these telescopes typically cost more. There are other instrumental factors, primarily having the right sky conditions (dark skies) and building on your experience, that will dictate what galaxies you are able to see. Training your eye requires a lot of practice and a commitment to observing on a regular basis. If you are looking for a new Telescope to purchase to observe both Planets and Galaxies, I suggest you read my comprehensive guide here. Best of luck! Other guides you may want to read:
- Can You See The ISS With A Telescope?
- Can You See Nebula With A Telescope? [What Can You Expect]
- Can I See Mars With A Telescope? [What You Should Expect]
- Can I See Neptune With A Telescope [And What Can You Expect]
- How Far Can You See With A Telescope? [It Depends On This…]
Hey, my name is Jeremy. I’m a passionate and seasoned astronomer who loves nothing more than observing the night sky. I also love researching, learning, and writing all things Space and the Universe. I created Astronomy Scope to share my knowledge, experience, suggestions, and recommendations of what I have learned along the way while helping anyone to get into and maximize their enjoyment of the hobby.