Pedestrians stopped, runners halted and drivers slowed down as they peered into the sky with their mobile phones drawn.
It was no meteorite or low-flying plane, but a drone doing its job: washing the windows of a glass building facade.
The latest technology in building maintenance uses high-tech drones instead of traditional window washers on ropes, a practice that is gradually gaining popularity in Canberra.
On Wednesday morning, the ANU complex on Marcus Clarke Street in Civic was receiving a "drone wash", much to the admiration of passersby.
Drone pilot Hugo Douglas operated his Chinese-made DJI M400 drone from the top floor of the building as a water jet attached to the undercarriage sprayed water at full force onto the dirty glass.
"The drone is fitted with a water hose and is powered by a motor in the van parked down here," he said.
Mr Douglas works for Famaso, a Victoria-based company that is one of the first in Australia to introduce drones for window and facade cleaning.
Mr Douglas and his site operator, Clinton Burgess, made the trip from Sydney to Canberra for the job. They have been regulars in the capital in recent months, with many work requests coming their way, including the drone cleaning of the AIS Arena in Bruce.
So, is drone washing picking up due to a lack of manpower in the traditional window washing profession? Mr Burgess strongly denies this.
"It is about the technology and safety involving minimum risks," he said, comparing it to the "risk on ropes".
Drone washing buildings, especially high-rises, requires Civil Aviation Safety Authority (CASA) approval, which must be applied for and obtained daily.
"A specific geo-fenced location is provided for the approval. I received one for today's job, and one of the conditions is that the drone can't fly higher than 140 feet," said Mr Douglas, who completed his Remote Aviation qualifications through TAFE.
The former postie turned drone pilot and his colleague begin by cordoning off the area below before flying the drone up the building using a transmitter.
"We have half an hour of washing time and it's powerful," the pilot said.
The pair has drone-washed nearly 25 buildings in Canberra so far.
While the risks to humans are limited when deploying drones, there is still one unique hazard these new age window washers face on the job.
Drones can still disturb hornets' nests.