But like an unhappy family putting on a brave face to mark what should be a joyful occasion, the fixed grins at Tidbinbilla masked some uncomfortable truths at Australia's famous tracking station.

The complex, just south of the national capital, has been operating on dwindling resources and fewer and fewer staff for several years as the cash-strapped US space agency NASA, which pays for CDSCC, squeezes the complex's budget.

Industrial strife is looming between Tidbinbilla's 92 technicians and their employer, the CSIRO, which runs the complex for the Americans, over a pay and conditions deal that has been stalled for months. One insider said senior management at the space tracking station were on the verge of "mutiny", incensed at the increasing tendency towards "automation", the running of the giant dishes without human supervision.

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CSIRO confirmed that staffing and budgets were in decline but pointed to $5 million in capital spending this year and last. The organisation also says that technological advances and the rationalisation of back room functions allow the station to run with fewer staff.

Tidbinbilla is one of just three deep-space network stations in the world, and the only one in the southern hemisphere, and NASA chief Charles Bolden came to town this week to celebrate the first 50 years and spruik the role it will play in the coming years, including with any human mission to Mars. But the station's funding has declined from $22 million in 2011 to $20 million this year and staff numbers have dwindled from 112 workers in 2011 to 95 employees this year.

There has been a reluctance among staff to talk publicly about problems at Tidbinbilla but Professionals Australia, one of the unions represented on site, says there is exasperation among staff members there at the dwindling resources available for the famous dishes.

"There is a general feeling that CSIRO could be advocating for a better funding deal from NASA for what is an invaluable site ... and that they should be providing some separate CSIRO funding for such an important installation," union official David Smith said. ''They love to get the reflected glory from the good news stories but not to ensure it is properly funded."

Mr Smith said there was also frustration among Tidbinbilla staff over the delay in approval of their new wage agreement, which must be signed off by the workplace authority, the Public Service Commission.

"Agreement was struck in December for a very moderate pay increase that involved significant compromises, 2.8 per cent, yet the government has not been able to deliver that outcome," he said. "It seems that the government is prepared to force a dedicated workforce towards a ballot for protected action rather than resolve this matter."

A commission spokeswoman said the agency was in the process of finalising its assessment of this agreement.

CSIRO spokesman Huw Morgan said the restructure at Tidbinbilla has been conducted with all parties involved and that much of the staff reduction had been enabled by technology rather than cost-cutting.

"The recent restructure at CDSCC of the management and staff structure followed a year-long consultation process with all parties, management, staff, CSIRO and unions," Mr Morgan said. "Staff reductions in that process were due to automation in some areas … or the functions amalgamated within CSIRO.

"NASA is currently operating the entire Deep Space Network on flat budgets in line with US government ... budgetary guidelines."