US citizens woke up this morning to the unbelievable news that their federal government would be shutting down all its “non-essential” services after the two houses of Congress failed to reach an agreement on a new budget. What this means in practice is that hundreds of thousands of federal employees will now face unpaid leave – and NASA’s workforce is among the most badly affected.

A staggering 97% of NASA’s 18,134 employees have been granted leave of absence, according to the Office of Management and Budget, quoted in the New York Times. This is the highest percentage of all the federal departments and agencies to be affected by the shutdown. Other federal workers affected include 94% of the 16,205 employees of the Environmental Protection Agency, along with 69% of the 13,814 working within energy.

“Due to the gov’t shutdown, all public NASA activities/events are cancelled or postponed until further notice. Sorry for the inconvenience,” read a rather understated tweet from NASA earlier today. Within the past few hours, the NASA website has also shutdown indefinitely.

Among the NASA employees to remain working during the shutdown are those critical scientists in contact with the International Space Station. Under NASA guidelines, those who remain working during an official government shutdown include those “performing work essential to prevent imminent threats to human life”.

Other excepted workers at NASA include a few researchers whose absence could result in serious damage to property. These individuals are selected by the directors of respective research centres. All other NASA workers are by law not permitted to work, even on a voluntary basis.

How long is this political and economic impasse likely to last? We put this question to our North America correspondent Peter Gwynne: “Government shutdowns in recent years have typically lasted only a few days, although the fact that level of political partisanship this year is significantly higher than in the past may cause a longer closure.

“More important than the shutdown is the forthcoming vote to increase the government’s debt level; if that fails, the US could go back into recession, probably taking the entire global economy with it.”