continued from yesterday – Part 1
The second day of the symposium started with an interesting talk by Professor Barbara Cunow of the University of South Africa (Unisa). Unlike many professional astronomers, she finds the time to continue her own amateur observations and has been monitoring Saturn for the past thirty years. She does it the old fashioned way, too – through the same six inch reflector she used as a school girl, sketching the view by hand. Over the last thirty years she has managed to observe the changes in Saturn’s rings for almost a full Saturn year, and spoke in depth on what causes our view to change from month to month.
I was the next speaker, presenting a paper on Astronomy Outreach in the Digital Age. Traditional outreach methods are here to stay, but the Internet is beginning to take their place as a default first-choice for more and more people. Unfortunately for those wishing to use the Internet to bring astronomy to the public, there are no hard and fast rules – the medium is too young and changes too fast. I introduced Urban Astronomer as an example of my own work in the field and discussed where I had gone wrong, and what lessons could be learned.
I was followed by Case Rijsdijk, who spoke briefly on the topic of stellar evolution. He walked us through a very massive star’s lifecycle, and looked at various possible endings, from neutron stars to black holes to quark stars and other even more exotic possibilities.
After the tea break, Professor Matie Hoffman (University of the Free State) took the podium. He spoke on the Assessment of the Expected Impact on Observing Conditions at Boyden Observatory of Light Pollution Associated with the New Developments in the Area. As discussed the previous day by Hendrik van Heerden, Boyden is a working observatory with a long international history. Boyden’s staff are actively involved in work on accretion disks, and multi-wavelength observations.
Proposed new housing developments near the observatory threatened to increase light pollution levels to the point where they would severely impact on the observatory’s usefulness. Professor Hoffman spoke at length on the report compiled by his department as part of the Environment Assessment Report required for construction to begin. He was pleased to report that the developers were receptive to the report and were eager to follow through on his suggestions on how to mitigate the effects of light pollution and light trespass. He also took a few minutes to announce the plans to build a new planetarium / dome theatre on the site of the observatory.
The next speaker was Heinrich Bauermeister from MMS Technology, the company contracted to build the antennae for the MeerKAT radio telescope array. He gave a detailed technical presentation on how the antenna dishes were constructed and designed. Moulds were constructed on site and the dishes were then constructed one layer at a time using modern aerospace technology. One of the delegates asked how quickly these dishes could be made and Heinrich answered that production could be ramped up to a single dish per week, per mould. This led to some discussion on how the three thousand dishes of the SKA would be constructed on time.
After lunch, Danie Barnardo spoke on Meteorites, Impacts and the Tswaing Impact Crater. Danie is a geologist at the Council for Geoscience, and is also vice-chairman of the Pretoria Centre of the Astronomical Society of South Africa. He explained the geology behind the various types of meteorite found on Earth, and discussed the formation of impact craters. After some discussion of the different rock formations found in various well known impact sites around the world, he moved on to Tswaing impact crater, near Pretoria. After a detailed discussion of the history of the crater, he showed a number of photographs and maps of the area.
The next speaker was Michael Neale, from the University of Pretoria’s department of Mining Engineering. Michael recently returned from the Space Resources Roundtable XI / Planetary & Terrestrial Mining Sciences Symposium at the Colorado School of Mines. He spoke to ASSA about the need for South African involvement in In Situ Resource Utilisation (ISRU), which means the mining and collection of resources from space, for use in space. The most challenging aspect of space flight is lifting material out of Earth’s gravity well. It is a hugely expensive enterprise, which severely limits the tools, resources and materials which astronauts can take with them. The principle of ISRU is that the mineral wealth of the Moon, Mars and Asteroids vastly exceeds that of Earth and should be much cheaper to harvest in space. He reported that there is a lot of interest from the mining industry internationally, and it seems likely that the next stage of human expansion into space will be led by miners and prospectors.
Case Rijsdijk then returned to deliver a second paper: Reporting Science. Case discussed the rift in South Africa between journalists and scientists, and considered various causes. The primary issues seem to be that there are practically no journalists with science training in South Africa (so that they usually don’t understand the scientist’s work, and end up misreporting it), and that scientists don’t appreciate the journalists position regarding deadlines, trust, etc. Bad science reporting is a problem because the general public usually lack the scientific background to be able to spot mistakes and are fooled by headlines like “AIDS vaccine on the way”. A particularly gruesome case was the attempt by the press to present a balanced case on Thabo Mbeki’s stance on AIDS vs the HIV virus — crackpot AIDS deniers were given the same prominence as real scientists who have done valuable work, leading many to take the crackpots seriously. Case then showed a few other examples of bad science reporting and suggested ways for scientists to improve their relationship with the press.
The final paper of the symposium was presented by professor Derck Smits, from Unisa, on the topic of Cosmic Masers. Although this year was widely celebrated as the 50th anniversary of the laser, the maser was discovered first, seven years earlier in 1953. After briefly explaining how masers are formed, through the stimulated emission of photons from excited aroms, he gave us a bit of history on the first discovery of a cosmic maser. Astronomers found a highly compact source of OH emission radiation in 1965, which was eventually identified as a maser occurring naturally from a vast cloud of ionised OH gas. Cosmic masers have also been identified as coming from the atmospheres of red giants and the cores of active galaxies. Derck then discussed some of his own recent work trying to identify the sources of some interesting cosmic masers which so far remain a mystery.
After thanking all the speakers for their time and effort, Johan Smit then formally closed the symposium. Delegates met up later for a casual evening’s stargazing at the Pretoria Centre’s observatory.
The following day, some of the delegates were given a tour of the HartRAO radio astronomy facility, and later on they visited the Tswaing Crater, but Urban Astronomer was sadly unable to attend.
Overall, the symposium was a great success, with a number of very interesting and informative papers presented. I look forward to the next symposium in 2012!