Dubbed the "Space Olympics", the world assembly of the Committee on Space Research, or COSPAR, will convene in Sydney's new billion-dollar convention centre in Darling Harbour.

"This is a ringing endorsement of our people, infrastructure and high regard in the global space community," Science Minister Greg Hunt said.

The successful bid defeated a field of cities including Shanghai, Valencia, Prague and Lausanne.

Australia's Chief Scientist Alan Finkel was delighted that Sydney will host COSPAR 2020.

"We come to the table with a bold vision for our nation's place in science – and through science, our place in space," Dr Finkel said.

NSW Minister for Tourism and Major Events Stuart Ayres said: "Up to 3000 international space experts will descend on Sydney with more than $10 million direct expenditure expected."

The announcement is expected to trigger further debate about whether Australia should have a space program.

Australia and Iceland are the only member nations of the Organisation for Economic Co-operation and Development without a formal space program, and Iceland is expected to join the European Space Agency soon.

New Zealand launched its space agency in July.

Professor Russell Boyce is head of space research at UNSW Canberra. Working with the Australian Academy of Science he led Australia's bid for COSPAR 2020.

"While we have no formal space agency we do, in fact, have a space program," Professor Boyce said.

"COSPAR 2020 will follow on from the International Astronautical Conference in Adelaide. All these activities in Australia should help reverse the brain drain in space science – these events are laying the seeds of an Australian space agency," he said.

Professor Boyce said Australia needed a co-ordinating framework, but it was probably too soon for the announcement of a formal agency.

COSPAR 2020 will take place within the timeframe that Elon Musk's SpaceX program is expected to start sending missions to Mars. The billionaire entrepreneur announced in September he would begin missions to Mars as soon as 2018 with hopes of landing humans there in 2024.

NASA and the European Space Agency are taking a longer time to get there, expecting to have humans on Mars by the late 2030s, but they expect that to start a permanent presence on the red planet.

Lyn Lewis-Smith, the chief executive of Business Events Sydney, which helped co-ordinate the bid, said: "We have vigorously pursued this important gathering, which will enable high-tech jobs to be further developed on our shores."

Space science activities in Australia include:

• In November, NASA and CSIRO opened the second of two 34-metre dishes at the Deep Space Communication Complex at Tidbinbilla near Canberra. That centre will play a central role in supporting the US space agency's missions to Mars and beyond.
• On Tuesday the Parkes radio telescope announced it had started listening in to our nearest neighbour, Proxima b, as part of the 10-year $100 million search for extraterrestrial intelligence announced by Professor Stephen Hawking and Yuri Milner.
• CSIRO is working as part of a global consortium to build the world's largest radio telescope, the Square Kilometre Array.
• In December the first Australian payload to the International Space Station will be delivered by science education start-up Cuberider.
• The first Australian-built satellites for 15 years will launch early next year to explore the thermosphere.
• UNSW with the Defence Science Technology Group is launching high-tech cubesat miniature satellites soon.
• CSIRO with UNSW, NASA's Jet Propulsion Laboratory and the DSTG have been using the Parkes dish and the 70-metre dish at Tidbinbilla to co-ordinate asteroid detection.