Backyard Astronomy: Introduction to the Stars
Written by Shawn Funk
The introduction of the James Webb Space Telescope earlier this year has no doubt captivated the imaginations of those who have seen its images, but you don’t need a big fancy space telescope to enjoy the rich starscape beyond our planet. Getting into the hobby is very easy and requires minimal start-up costs.
Like any hobby, you can spend thousands on astronomy gear, but it doesn’t and shouldn’t be expensive for a newbie. You can start your journey for free by simply looking up at night. Start easy; learn the constellations that are visible in your sky. I recommend buying a planisphere; it will show you the positions of the stars and constellations for any given time throughout the year. You can make your own with a template or buy the one from Chapters for $20. Make sure you buy the one calibrated for your location. For example, Lethbridge is 49 degrees latitude. My planisphere is calibrated for 42 degrees latitude and it works fine.
When you get bored of naked eye observing, find an old pair of binoculars and turn them to the sky. Use the binos with your planisphere and star charts, then begin checking off deep-sky objects. Cruise through the Orion Nebula your first night out, then score some honey at the Beehive star cluster the next. I used an old pair of 7×50 that were laying around the house and a planisphere to learn the skies. The total investment was $20. Protip. The numbers on your binoculars refer to the magnification and the size of the outer lens, called the objective lens. Thus, the binos I used were 7x magnification with a 50mm objective lens. Low magnification viewing is the best for scanning because you can see a greater swath of the sky. Higher magnification binoculars are unnecessary. They are harder to keep steady and they have a smaller field-of-view (FOV).
It is amazing how many more stars you can see with a pair of binos compared to the naked eye. Even so, eventually, you will want to upgrade. Backyard enthusiasts are always pushing their wallets to see deeper into space. Buying your first telescope can be intimidating. Here are a few tips for those who want to take their viewing to the next level.
Telescopes are costly. I purchased most of my gear on the used market to save costs and preserve resale value if I ever decide to sell. You will also need to buy a few good eyepieces and a diagonal. Some sellers will include these with the scope. I recommend buying a low-power eyepiece first, then filling out your collection with 2 or 3 more useful magnifications. You will find that your low-power eyepiece will be your most used eyepiece.
There are more than a few different styles of scopes: refractors, Dobsonian, Newtonian, Schmidt-Cassegrain. I favour refractors, but each telescope design has different strengths and weaknesses, so you must research to find the scope that suits your needs. Protip. The capability of a telescope is measured by its ability to gather light. Thus, the bigger the aperture (width) of the objective lens or mirror, the more light that lens or mirror gathers. A good starting point for your research is the Cloudy Nights website. This site contains hundreds of threads about astronomy. www.cloudynights.com
Okay, so you have your gear. Now it is time to take a look and it is cloudy, of course. Wait for a clear night. Dark skies are your friend; seek them out. If you can’t escape the city, that’s okay there is plenty to see, even in light polluted areas. I have spent hours just looking at the details on the moon; many of the planets can also be seen in the city. Jupiter, Saturn, and Venus are in the sky right now; check your charts to see the best time to view them. Some of the brighter deep sky objects are also visible. The Andromeda galaxy, the ring nebula, and the Hercules globular cluster, among many others, are very easy to spot in town.
There are thousands of deep sky objects to search for in the sky. I will warn you now that you will not see the fantastic images of galaxies, nebulas, and star clusters on the NASA website. This is because many deep sky objects are so faint that they look like small fuzzy patches through your lens. It takes some patience to find these objects in the sky because they are so faint, but with practice and a dark sky, your eyes will adjust, and you will learn to see the details in the fuzzies. It is gratifying when you finally find the object you are looking for.
The best way to find deep sky objects is with a detailed star chart that shows their location and a dark sky to observe. An excellent field guide for stargazers is called Nightwatch by Terrence Dickinson. This book contains a wealth of information about the hobby and detailed star charts that span the entire night sky. It is a durable ringed book that is great for the field. Be sure to explore the Messier catalogue of deep sky objects; it is a list of 110 deep sky objects that can be seen with binos or a small telescope. I can see many of these objects with 7x50mm binos and all but a few in an 80mm telescope. Take notes as you observe. Try to describe as much as you can. Including the date, time, and a small sketch will go far when you reflect on your observations. Protip. Do not close your unused eye when looking through a telescope. Cover one eye with your hand but do not close it. This will help prevent eye strain.
If you are interested in learning more about astronomy, you can visit the Oldman River Observatory in Popson park. The Lethbridge Astronomy Society also holds public viewing sessions on the last Saturday of the month at 7:30 pm from October to February. Here you will have access to some of their telescopes, and you will get to meet other enthusiasts who love astronomy. Lastly, for those interested in the science of astronomy, there are some excellent astronomy classes at the U of L that explore topics ranging from the life cycle of stars, Newtonian mechanics, and the cosmic microwave background.