Observing

Introduction to Astronomical Observing

Astronomy is the scientific study of the planets, stars, galaxies and the universe. An astronomer is an individual who has an educational background and profession that relates to astronomy. There are many branches or specialties in the field of astronomy.

An amateur astronomer is an individual who studies astronomy as a hobby. There are many thousands of amateur astronomers all over the world. Some are casual and devote a few hours a year to the subject. Others devote many hours a week to their hobby.

Amateur astronomers have contributed significantly to the field. For example, volunteers who look through images from the SOHO spacecraft on the web have found most of the more than 5,000 comets that SOHO has spotted near the Sun. Imagine discovering a major comet and having it named after you. This happened to Alan Hale and Thomas Bopp, who independently discovered the same comet on the same night in 1995. You may know it as Comet Hale-Bopp!

Observing is the process of looking out into the universe. We can observe at night or during the day; however, most observing happens at night. We can observe with just our eyes, with binoculars, telescopes, or radio telescopes. There are many wonders to look at.

Learning about the night sky is a rewarding experience. The best place to start is learning the constellations, how and when to find them. Start with the easy ones like the Big Dipper, Orion, and Cygnus. The important thing is to understand that the stars and constellations have seasons. Certain constellations are visible at night only during certain times of the year. (The months traditionally tied to the zodiac constellations are actually the times when the Sun is in front of them, so those constellations are hidden in daylight then, not overhead at night.) The next step is to use those constellations to find the planets, globular clusters, open clusters, planetary nebulae, galaxies, variable stars, double stars... While the planets move from constellation to constellation, the clusters, galaxies and nebulae stay put. M13, the great globular cluster, will always be in Hercules.

Constellations - This is a great place to start. There are a lot of books that can help you learn the constellations. Also consider picking up a planisphere. These are great tools for learning the constellations since they can be set to the current day and time and show you what is up there "now".

Star Hopping - Once we learn the constellations and some star names, we can hop from star to star to find other items. For example, if I say Saturn is in Gemini, most amateurs will know which direction to look. The Orion Nebula is the middle "star" in the sword of Orion. When you look through a telescope you will see there is more than one star there. On a clear night a small telescope shows four stars in a tight group called the Trapezium, wrapped in a cloud of glowing gas. It is one of my favorite objects to look at through a telescope.

The Moon - The Moon is a great first object to study. It is very easy to find, and there is a lot of detail to see. A very rewarding time with minimal effort. For the best views of the Moon through a telescope you should choose a night when the Moon is not full. Looking at the line between shadow and light will give the best contrast. That is where the Sun is rising or setting on the Moon, so the shadows are the longest.

The Planets - Some of the planets are easy targets too. They also can reap rewarding views with somewhat minimal effort. Knowing where the planets are also impresses friends when out at night. You can say "hey, look at Saturn" and point to it. Looking at Saturn through a telescope for the first time is one of the greatest experiences for just about every observer.

Deep Space - Deep space objects are more difficult to find and sometimes difficult to see even after you find them. The cool thing is that once you do, you will be looking at something extraordinary in the cosmic sense. For example, globular clusters have hundreds of thousands of stars. Nebulae are clouds of gas and dust: some are places where new stars are forming, and others are gas thrown off by dying stars or blasted out by stars that exploded. Galaxies are the most difficult to see but can hold billions, even trillions, of stars!

Equipment - You already have the first equipment you need to start observing, your eyes. Start out learning the constellations, where the planets are, when the Moon rises and sets. There is a lot to see with just your eyes. Binoculars are also a good first investment. There are a lot of things that can be seen with binoculars. If you have a pair, go out and look at the Moon, pan around the sky, and you will be surprised how many stars there are. A telescope is the obvious next investment.

Books - There are a few good books that can get you started. We have a list of our favorites here.

Where to get more information - Visit your local astronomy club. When I was starting out I learned more about astronomy and telescopes from the club than I could in any book. Members showed me their telescopes, discussed different models, showed me around the night sky. I am happy I went to the club before I purchased a telescope because the one I had in mind was the wrong type for what I enjoy doing.

Another great place to learn about telescopes is at star parties. These events are held all over the country and the world. They draw anywhere from a few dozen to hundreds of amateur astronomers.

We hope you will use these pages to learn about astronomy. These pages are meant to introduce you to astronomy and get you started observing the night skies with a telescope. Use the site menu to navigate to other astronomy topics.