Thank you for your interest in the Johannesburg Centre of the Astronomical Society of Southern Africa. We would like to tell you a little about ourselves. 

Who are we?

We are a group of enthusiasts who come from all walks of life and share a common interest in Astronomy, an interest that may be deep and intense or slight and casual – we welcome and cater for all. Whatever aspect of astronomy turns you on – be it that you are purely interested in appreciating the beauty of the cosmos, wish to contribute to the advancement of science, enjoy tinkering with gadgets, want to talk about cosmology, or whatever else – we have a place for you. Some of us own telescopes, some binoculars and some only a pair of sharp eyes with which to view the heavens.

As with several similar centres scattered in and around South Africa, the Johannesburg Centre is independent of but affiliated to the Astronomical Society of Southern Africa, the "parent body" generally referred to as ASSA.   

We hold a monthly general meeting at 20h00 on the 2nd Wednesday of each month (except December). Our normal venue is the Sir Herbert Baker Library Building on the site of the Old Republic Observatory. The address is 18A Gill Street., Observatory, Johannesburg – entrance is via Innes St. See map and directions here >>

These meetings usually take the form of a lecture by a guest speaker, a debate or a film show, with refreshments and socialising afterwards. Public viewing evenings are (weather permitting) held at the Observatory on the Friday closest to First Quarter Moon, starting at about 20h00. The Centre’s monthly newsletter “Canopus” provides full details of these meetings, as does this website. The general public are particularly encouraged to come to both the general meetings and the viewing evenings: meet us, look through the Centre’s telescopes and find out more.

Why join?

Membership of the Centre confers several benefits. Not least of these is the opportunity to have contact with friendly, knowledgeable individuals who share your interests in astronomy. We freely impart our knowledge, ideas, enthusiasm, advice and experience. We encourage you to do likewise. 

As a member, you would have access to our facilities, including a library dedicated to astronomy and related disciplines. Successful completion a simple “driver’s course” will allow you the use of our instruments.

The Papadopoulos dome contains two refractors and a Cassegrain on a common mount.			The Jacobs dome contains a large Newtonian

Apart from this, you get to participate in our other events and activities. Our ties to the Planetarium are also advantageous. Have you just purchased a telescope? We can help you to learn to set it up and use it. Are you thinking of purchasing one? We can help you make the right choice. Want to know what’s up there? Need to discuss your theories? We are here!

Activities

In addition to the activities already mentioned above, our members - according to their individual needs and interests - are involved in a variety of activities including the following…  

Telescope Making

Classes are conducted on an ongoing basis. With the application of some effort and a really modest outlay in cash, you too can build a fully functional telescope that will keep you happily observing for years to come. A large number of instruments have been completed under our guidance over the last several years. These range from the basic and plain to the sophisticated, beautiful and even computer-controlled: the sky is literally the limit.

By building it yourself, you can not only save substantial sums of money, but also tailor-make an instrument to your own specific needs. The satisfaction of fashioning an optical surface to an accuracy of a few millionths of an inch with your bare hands is matched only by the pride of accomplishment when you stand back to survey your personal creation, and the enjoyment of observing with something you have built yourself. The first glimpse of the heavens through your own home-built telescope is truly an experience without parallel.

Even if you are not interested in building a telescope, visiting us may be worthwhile - you can learn how a typical astronomical telescope works and be better prepared for making purchasing decisions.  Find out more here >>

Group Activities and Excursions

These range from star parties (informal gatherings for deep-sky viewing, often at dark sites", through visits to observatories, impact craters and other places of scientific interest, to meteorite hunting and even eclipse viewing expeditions.  We take advantage of circumstances such as visiting scientific luminaries, or astronomical events such as meteor showers and the appearance of comets to hold extra-ordinary meetings, observing sessions and gatherings. Courses in constellation recognition, basic astronomy, use of instruments and so on are offered whenever there is sufficient demand. There are also purely social activities, exemplified by the end-of-year “solstice party”.   Once a year, we host the ScopeX Telescope and Astronomy exposition. Browse our site for more information.

Why not involve yourself in contributing to our newsletter? Researching areas of interest to you and putting them forth for others to enjoy is a fulfilling and educational experience. Find back issues here >>

Photographic and electronic imaging

This is a field of endeavor that - while it can certainly begin with humble and inexpensive equipment - generally attracts those looking for a challenge. Some of our members have even built their own specialist astronomical cameras and tracking platforms dedicated to the task.  Their results are showcased on this site from time to time.   See our gallery >>

Participation in scientifically valuable observing programs

Amateur astronomers can and do provide input to professional programs.  Surprisingly, many of these need only simple equipment such as binoculars (or even the naked eye!) to accomplish.  Examples of exciting and fulfilling programs in which our members are active include:

• Approximately one third of the world’s solar observers are based in Southern Africa. They make regular, detailed observations of the sun, recording sunspots, solar flares and electromagnetic disturbances.

• Lunar Occultations occur when the Moon passes in front of a star. By accurately timing the disappearance and reappearance of the star, knowledge of both the Moon’s orbit and the positions of the stars can be greatly refined. Observations of Grazing Occultations – during which the stars just skim the edge of the Moon, rather than being hidden entirely – additionally assist in accurately mapping the Polar Regions of the Moon.

• The observation of Variable Stars is probably the most important and exciting contribution that amateurs make to science. There are a number of reasons why a star may vary in brightness and a variety of behaviors – some change brightness in a regular cyclic fashion with periods ranging from days to years, whereas others may undergo sudden, rapid and irregular brightening and dimming.  Amateurs around the world simply record their estimates of the brightness of a given variable star with respect to adjacent stars of known brightness and forward them to a global clearinghouse for use by professionals.