On Sunday the world’s largest radio telescope, the Five-hundred-meter Aperture Spherical Telescope, or FAST, officially went into operation. The technical marvel, located in China’s southwestern Guizhou province, has attracted attention worldwide, but scientists at the telescope are worried it might attract visitors who will interfere with the area’s radio waves.

According to state broadcaster CCTV, in recent tests FAST picked up signals from a pulsar star 1,351 light-years away (roughly 85 million times farther than the distance between the sun and the earth). In theory the radio telescope can reach the very edge of the universe, over 13.7 billion light-years away.

But picking up signals from that far out into space requires radio silence in the vicinity of the telescope. The location of FAST was chosen because it was not near any power lines or industrial sites that might cause interference, and more than 9,000 villagers were moved out of the immediate area to make sure the telescope could operate at peak performance.

The government of Kedu, the nearest town some 5 kilometers away from FAST, seemingly has other plans, however. Saying it wants to “seize the great opportunity of the FAST project,” it has been trying to turn the town into an astronomy cultural park, with facilities such as an observation deck, industrial park, tourist center, and education sites.

In the town, home to a population of 45,000 residents, some 14 hotels have been established over the last eight years. Chen Keying works at a Kedu hotel called Sky City. The 28-year-old told Sixth Tone the establishment opened last year and was financed by a businessman from Zhejiang province in eastern China. “More and more tourists come here because of the radio telescope,” she said. “More than 10 rooms have been reserved for the coming national holidays.”

This small tourist boom is a concern to the scientists who work at the telescope. Zhang Shuxin, the office director of the FAST project, was quoted by online news outlet Jiemian.com on Sunday as saying he fears that the rising number of visitors and their electronic gadgets will influence the radio telescope’s effectiveness.

“The scientists do have a valid concern,” May Chiao, chief editor of astronomy at the scientific journal Nature, told Sixth Tone by email. “Mobile phone signals and WiFi operate at frequencies within the telescope’s operating range, so phones would interfere with the faint signals that the scientists are trying to detect from the edge of the cosmos.”

Chiao added that in Australia, the Parkes radio telescope in New South Wales had been picking up mysterious signal noise since 1998. Only last year was the source identified as a microwave in the facility’s break room.

Earlier in 2015, Nan Rendong, the chief scientist of the project, said that even a plane that is sending messages to the ground dozens of kilometers away could be akin to an electromagnetic storm for FAST.

To make sure the tourists don’t interfere with FAST, the Guizhou department of radio management released regulations effective Monday that forbid wireless communication in the area surrounding the telescope.

“Tourists cannot take equipment like smart phones, watches, and cameras onto the observation deck,” Ai An, an employee of a local tourist company, told Sixth Tone, adding that around 150 tickets for the deck have been reserved online.

But these difficult-to-enforce measures haven’t stilled the fears of FAST scientists. An unnamed engineer told Jiemian that they fear interference from tourists might turn into a large waste of money. “It is estimated that the daily operation of FAST costs 400,000 yuan,” they said. “If one day is wasted, 400,000 yuan just disappears.”

Additional reporting by Sarah O’Meara.

(Header image: An aerial view of the Five-hundred-meter Aperture Spherical Telescope (FAST) in Pingtang, Guizhou province, Sept. 24, 2016. Wu Dongjun/VCG)