The SKA Site Advisory Committee's decision to recommend South Africa over competing bidder Australia was very close, a source familiar with the process told the journal Nature.
"This is not an enormous preference for one over the other," the source said.
And the project's member states -- China, Italy, the United Kingdom and the Netherlands -- said they have yet to make a final decision on where the telescope will go, and may not have a final choice until April.
The $2.1-billion SKA radio telescope will be made up of about 3,000 separate dishes, each 50 feet in diameter, covering a square kilometer or almost 250 acres.
The South African site has some advantages, such as lower construction costs and the fact it would sit at a higher altitude, but the Australian site would be cheaper to insure and less likely to be encroached on by future development, experts said.
Members of the SKA's board will meet March 19 in Manchester, England, to consider the scientific panel's recommendations, Nature reported.