Luciano Pazzi
Early this year, Nigel Observatory (a private observatory built in the suburbs of the East Rand near Johannesburg) was shutdown and its equipment sold off. I visited the owner, Luciano Pazzi, hoping to buy some of his observing gear and ended up getting a tour of the facilities along with a brief history lesson. Luciano’s home is warm and hospitable, and we chatted for hours about South African astronomy and his impressions of how it had changed over the decades.
Luciano was born in a small town south of Bologna, Italy, in 1943. His love of astronomy goes back as far as he can remember. At the age of ten he was observing the Moon with a homemade refractor, assembled with spectacle lenses. At the age of eighteen he immigrated to South Africa, after which the serious side of his interest in astronomy emerged. He’s been involved with the timing of lunar occultations with a portable 0.1meter Newtonian since 1968. He has participated in many expeditions to observe grazing occultations.
Until recently, Luciano owned a fully-fledged observatory located in his backyard in Nigel. The main instrument of the observatory is a 0.3-meter Cassegrain that is used to photoelectrically observe a number of variable stars. He has authored and co-authored over twenty, internationally recognized, papers in various scientific journals in South Africa and abroad. Luciano is particularly interested in eclipsing variables of the RS Canum Venaticorum type.
Luciano kindly agreed to let me interview him:
Could you tell me a little about the construction of the observatory? It’s a solidly built, well equipped structure. What motivated you to start such a project? How long did it take, and how has it evolved since you first started construction?
The observatory has a 4m circular brick base capped by a steel ribbed dome covered by a skin of galvanized sheeting. The dome rotates on rollers and is driven by electric motors. The shutters, which are 1.2m wide extending past the zenith, are also motorized.
This is actually the second dome constructed for the observatory; the first was on a farm just outside Nigel in the sixties. A disagreement with the farmer prompted me to move the observatory in my own yard. The dome had to be left behind. The observatory building was constructed as a spare time project and it took the better part of two years to complete.
The present building has not substantially changed much from its first inception, but it has been made more comfortable by adding various gadgets such as fans, dimming lights, extra power points, etc.
The contents of the current observatory have changed over time, with the 31cm Cassegrain being the current primary instrument. What other equipment did you build, acquire and use over the years?
The original instrument of the observatory is the 31cm but in form of a Newtonian mounted on a German equatorial mount with a rudimentary guiding system (using synchronous motors). During the the early eighties I added a photoelectric photometer to the equipment, together with various eyepieces and a computer. In the mid nineties the telescope was transformed into a Cassegrain operating at the Nashmith focus and the mount was changed to an English fork.
The drive system uses stepping motors with provision for fast slewing. Acquisition of objects was originally done (in the eighties) with digital encoders that was later changed to an analogue system using large setting circles. I found the analogue system more accurate and easier to use than the digital system. The hyperbolic secondary was ground, polished, and figured at the observatory (two attempts and almost two years). Most of the parts were manufactured at the observatory.
You’ve published over 20 papers in various journals around the world, many of which can be found on ADS (http://adsabs.harvard.edu/index.html). Do you consider yourself a professional astronomer, or dedicated amateur? Aside from a passion for astronomy, what scientific background and education do you have?
I cannot consider myself a professional astronomer, as I do not get paid for my efforts, but the appellative of “amateur” smacks of fumbling useless efforts. I prefer the term “Part Time Astronomer”. I have no formal astronomical training. I attended an agricultural high school in Italy and I almost have a BCom from Unisa, just missing one major.
The observatory has been used both for scientific work and for public outreach, and operated for many years. Were there any special moments that stand out in your memory from this time?
One of the most vivid memories, connected with the observatory, is the expedition to Messina (Northern Transvaal) to observe the grazing occultation of Antares by the Moon, one of the first grazes observed in South Africa. The photoelectric observations of W Cru in the early nineties, that generated a number of related papers in scientific journals, is also a fond memory. The visit of some schools in the early days is also important to me. There are actually so many good memories associated with the observatory that is difficult to mention all of them.
You mostly study variable stars and are particularly interested in RS Canum Venaticorum eclipsing variables. Could you explain what causes this type of star’s variability, and what makes it distinct from other types? Is there any particular reason why you’ve chosen this type to study?
The setting-up of the photometer at the observatory was much encouraged by some astronomer in the US, such as Dr. D Hall from Vanderbilt University, Prof. Plavec UCLA, and many more, they were involved in the new field of peculiar spotted stars, so I got involved as well.
This brief description of RS CVn is extracted from my paper of TY Pyx:
The RS CVn binary systems usually consist of a late type chromospherically active evolved star tidally locked to a main sequence or subgiant companion that may also be active. There are usually long-term period changes associated with RS CVn systems. Frequently a wave-like fluctuation is present and is most evident in the portion of the light curve outside eclipse.
There are probably many better explanations on the Internet.
I have ambitions towards building my own observatory, and perhaps even conducting meaningful research. What advice would you offer somebody taking this path?
It is extremely convenient to have a fixed observatory, as it avoids the need to carry the instrument in and out of the house and it avoids the risk of bumps that move the optical path out of alignments. However a brick and mortar structure cannot be dismantled if you move and might even detract from the value of your property. The best compromise is a roll-off roof (access to the all sky) mounted on a structure that can be easily dismounted when you want to move.
Reading through Sky & Telescope and other periodical it seems that everybody is taking fantastic pictures of the universe. As lovely as this is, what is the scope of it? I have not seen a single paper dealing with lovely views of the universe in any scientific journals. Optical and technical papers are common but not a single one regarding a beautiful picture! There is a lot of research that can be done, research that is sought after by the astronomical community. Of course I am biased toward variable stars, but there are literally thousands of interesting objects whose research can lead to a better understanding of the universe as a whole. My suggestion is to get in touch with professional astronomers or organizations that can advice about useful research. In my personal experience, the US astronomers are the most helpful and willing to give advice to amateurs.
Comments? Questions? Why not mail me at [email protected]