The presence of Aldrin, alongside two European astronauts and a Russian cosmonaut, guaranteed there was standing room only in the International Astronautical Federation's (IAF) Global Networking Forum (GNF) meeting room.
Aldrin said that he had hoped that all three members of the Apollo 11 crew - Armstrong, Mike Collins and himself - would have been around to celebrate together the 50th anniversary of the first Moon landing in 2019.
"His one ‘small step' changed the world and will forever be remembered as a landmark moment in all of human history," said Aldrin.
He also showed his film ‘The Apollo Dream', adding that Armstrong, who died in August, had left the world a strong and lasting legacy which everyone had a duty to fulfill.
After his presentation, European astronauts Christer Fuglesang and Paulo Nespoli, along with cosmonaut Sergei Krikalev, gave short presentations on their spaceflight experiences and then answered a variety of questions from the audience.
The GNF, an evolution and transformation of the former IAF Cluster Forum, proved a big success throughout the week, attracting a large number of delegates to a range of meetings and sessions.
It included several dedicated days and sessions, including a Heads of Agencies press conference, an Industry Day, and sessions looking at the Social Impacts of Human Spaceflight and Space Careers, as well as the Astronauts' Day.
During Industry Day (Tuesday, 2 October) panels of industry and space organisation experts debated the economic impacts of Satellite Navigation Systems, Earth Observation challenges and the new European-developed rocket Vega.
Among the items that came up for discussion during the session on ‘Economic impacts of Satellite Navigation Systems' was the dispute over satellite navigation frequencies between China and Europe.
Paul Weissenberg, Deputy DG, Enterprise and Industry Directorate-General of the European Commission, stated that it had been agreed to take their dispute to the International Telecommunication Union (ITU) by the end of this year.
The GNF was also the location on Wednesday for the IAF's extraordinary session at which space-flown flags were handed to member organisations to commemorate the Federation's 60th anniversary.
The flags - flown on Soyuz TMA-20, the International Space Station, Space Shuttle Endeavour (STS-134), and China's Tiangong-1 and Shenzhou-9 spacecraft - were presented to IAF member organisations by President Berndt Feuerbacher.
The above is one of a series of daily reports from the International Astronautical Congress 2012 held in Naples, Italy, written by Clive Simpson for the Paris-based International Astronautical Association (IAF) and first appearing on the IAF website