China's Five-hundred-meter Aperture Spherical Telescope, known as FAST, may provide understanding of the origin and structure of the universe, and accelerate and even revolutionize the search for life beyond Earth, a renowned US theorist on alien intelligence said on Saturday.

Douglas Vakoch, president of METI International, an organization that promotes sending messages into space in search for extraterrestrial intelligence, said that astronomers worldwide will be invited to use the Chinese observatory if their proposals successfully pass competitive reviews.

"By opening FAST to use by the broader international community, China is demonstrating its commitment to fostering astronomy as a global scientific enterprise," he said, adding that it may lead to "discoveries beyond our wildest imagination".

As for FAST's scientific missions, Vakoch said it will be used to look for the signatures of complex organic molecules in interstellar space, which will show how widely the basic building blocks of life are distributed throughout the cosmos.

"For over a half-century, astronomers have been using radio telescopes to answer the haunting question: Are we alone?" he said. "But astronomers face a daunting challenge: The signals they seek are so weak that an incredibly sensitive telescope is needed to detect them."

"FAST's innovative design and huge collecting area give it unsurpassed speed and sensitivity, making it vital to the search for extraterrestrial intelligence in the coming decades," Vakoch said. "We can expect China to become a world leader in the search for extraterrestrial intelligence because of its demonstrated commitment in building FAST."

However, FAST will not initially be outfitted with the signal processing capabilities to search for aliens, he said; such technology will be added at a later stage. But when that happens, FAST will be able to scan the heavens for signals that "can't be created by nature, but only by advanced civilizations".

Based on the recent history of radio telescopes, he also predicted that FAST will lead to "a dramatic increase in the number and variety of pulsars discovered".

Pulsars, one of FAST's main scientific targets, are dense rotating stars that act as cosmic clocks, as they emit pulses regularly, like metronomes.

This could also provide scientists with the capability to detect gravitational waves, or ripples in space-time, from pairs of massive black holes, since FAST has the potential to precisely measure tiny changes of the pulsing rates of pulsars as gravitational waves pass by.

Vakoch highlighted FAST's role in underpinning China's space program, noting that the country has made great breakthroughs in space exploration, such as putting humans into Earth orbit and having astronauts dock with an orbiting module as a first step toward developing a Chinese space station.

"With the opening of FAST, China continues to demonstrate that it is a world leader in space exploration - now from an Earth-based observatory, as well as from space," he said. "Astronomers around the world can be grateful to China for creating an observatory that may lead to discoveries beyond our wildest imagination."