Amateur astronomy, also called backyard astronomy, is a hobby whose participants enjoy watching the night sky (and the day sky too, for sunspots, eclipses, etc.), and the plethora of objects found in it, mainly with portable telescopes and binoculars. Even though scientific research is not their main goal, many amateur astronomers make a contribution to astronomy by monitoring variable stars, tracking asteroids and discovering transient objects, such as comets. Such efforts are one of the relatively few ways interested amateurs can still make useful contributions to scientific knowledge.
Large encounters of amateur astronomers in dark places suitable for sky viewing are called star parties. Amatuer Telescope Makers (ATM's) combine the hobbies of observing and designing, building and constructing telescopes. This hobby was pioneered in America by Russell Porter, who later played a major role in design and construction of the Hale Telescope.
Some good books for amateur astronomers to start with:
- The Stars, a New Way to See Them -- H.A.Rey
- NightWatch, 3rd edition -- Terence Dickinson
- The Backyard Astronomer's Guide, 2nd Edition 2002 -- Terence Dickinson & Alan Dyer
- Turn Left at Orion -- Guy Consolmagno
- Skywatching -- David H. Levy
- Seeing in the Dark -- Timothy Ferris
With binoculars it is possible to see many deep sky objects (DSO's) albeit, not terribly well. Holding the binoculars can produce a shaky image. One way to improve the view is with the aid of a sturdy tripod mount to steady the view through the binoculars. Binoculars are still limited in range, however, most of the Messier catalogue should be visible and a great many NGC's as well, especially near the Milky Way.
With a telescope, the sky really comes alive, especially one that has an aperture of six inches or more. Some amateur telescopes are built by their owners from scratch. But many good quality telescopes can be purchased from reputable companies. Thousands of DSO's are visible in a telescope and the determined amateur with a large (about 41 cm) telescope can push this to tens of thousands or more.
Another type of telescope to consider, especially if the amateur is observing with children, is a wide field telescope. This is typically a short tube reflector. This type of telescope has an aperture of only 80 to 120 mm (3 1/4 to 4 3/4 inches), but is easier to target an object, since it offers a much wider field of view. With the aid of high power lenses (i.e. eyepieces), the amateur can zoom in on planets and some of the closer DSOs. It is the best of a blend of a telescope's narrow long range light gathering ability with a binocular's wider field of view. With any telescope, though, the mount is the most important feature. A tripod that doesn't shake every time one uses it is a must. Too many amateur astronomers give up because they have a hard time targeting an object. If the mounting tripod is rock solid, the amateur can enjoy their time observing the heavens instead of fighting with the telescope.
The next step in an amateur astronomers quest for more space adventure comes with the purchase of a good camera for Astrophotography. Starting out with a good 35 mm camera with a 50 mm lens mounted on a tripod and using a cable release and 400 or faster speed film, the amateur can capture some nice pictures of the planets and some larger nebula, like the Orion Nebula. Some of the larger comets and prolific meteor showers can be photographed this way as well. As one progresses, cameras can be mounted directly on to telescopes, capturing on film many DSOs. Special films and even the technique of hypering the film has been employed by the amateur. Many publications accept these astrophotos in their magazines, ie. Astronomy Magazine.
Example of an amateur astrophoto taken of the comet Hale Bopp using a standard 35 mm camera with a 50 mm lens, using 400 ISO film. Image was taken for 10 seconds on a tripod using a shutter cable release!
See also: Observation\n zh-cn:业余天文学