Li Baoda is part of the group of Chinese scientists who study and record pulsars using the largest radio telescope in operation in the world, Fast, an acronym in English for “Five Hundred Meter Aperture Spherical Radio Telescope”. In the year 2026, his team recorded the first example of a black widow binary pulsar discovered entirely by a local team in Guizhou province.
Fast is located in Pingtang, in the interior of Guizhou, in a karst depression, a phenomenon that occurs when the roof of a cave collapses, leaving a bowl-shaped hole. This cave is first formed by rainwater that infiltrates and dissolves soluble rocks, such as limestone, dolomite or gypsum.
The project’s conception emerged in 1993, when astronomer Nan Rendong presented the proposal to build a new generation radio telescope during a radio astronomy conference in Japan.
Over the next ten years, his team traveled the interior of Guizhou, mapping more than 3,000 natural depressions until selecting the one in Pingtang. Work began in 2011, and the telescope went into operation in September 2016. Unlike optical telescopes, Fast is designed to capture radio waves coming from other regions of the universe; the larger the structure, the greater the amount of signal that the instrument can record.
Pulsars are neutron stars that emit two radio beams from their magnetic poles. Since its inauguration in 2016, the telescope has identified more than 1,300 pulsars, surpassing the sum of all other telescopes on the planet in the same period. Li Baoda’s team contributed 22 new millisecond-type pulsars, distributed across six globular clusters, which are sets of stars that orbit the center of the galaxy. Fast’s most recent discovery, made this year, is a system of pulsars with an atypical rotation pattern, in which three stars interact with each other.
Mining celestial data
“A single day of observations generates tens of thousands of candidate signal graphs,” explains Li Baoda. “Computer screening has a high error rate, so researchers have to manually review millions of images. Some colleagues have looked at millions of frames without being able to detect a single new signal.”
The researcher says that his work is like that of a gold miner, only with data. “We have the instrument and the raw data, but without researchers to analyze and interpret it, unknown celestial objects and unprecedented scientific phenomena would remain unknown,” he says.
The black widow pulsar that he and his team discovered is a binary system in which the neutron star releases stellar winds that gradually erode the companion star’s atmosphere, leaving only the core exposed. The name comes from the spider that sometimes feeds on the male after mating.
Binary pulsars make up about 30% of all known pulsars; those of the black widow type represent only 5% to 10% of this subgroup. These are systems that make it possible to study the evolution of neutron stars in extreme conditions that cannot be recreated in the laboratory. “The articles were published and received high recognition from astronomers”, says Li Baoda.
“I feel a special responsibility to use Fast to boost national astronomical research and stimulate local technological innovation,” says Li.
Brazil and China in international astronomical cooperation
In recent years, China has opened Fast observation time to foreign scientists. Brazil is perhaps China’s main partner in this area. Among the joint projects of the two countries is Bingo (acronym in English for Observations of Baryon Acoustic Oscillations in Neutral Gas), a Sino-Brazilian radio telescope designed to map neutral hydrogen in the cosmos and investigate so-called dark energy, which is related to the expansion of the universe.
In June 2025, Bingo’s main structure was sent from China to Paraíba, beginning the construction phase of the radio telescope in the country. Bingo, which may operate in a complementary way to Fast, is developed by researchers from China, Brazil, the United Kingdom, France and Switzerland.
The two countries also created the China-Brazil Joint Radio Astronomy Technology Laboratory, managed by the Chinese state company CETC in partnership with the Federal University of Campina Grande and the Federal University of Paraíba. The difference with projects such as Alma (Atacama Large Millimetric/submillimetric Antennas Set), from the European Union in the Atacama Desert, in Chile, is that Bingo is co-owned by Brazil and China. At Alma, Chilean astronomers can participate, but the country is only a host of the European project, not a co-owner.
“The meeting of diverse ideas considerably accelerates scientific progress”, says Li Baoda, when asked about the importance of international cooperation in astronomy.
Fast’s objectives also include the search for extraterrestrial civilizations. “Personally, I believe that the existence of extraterrestrial civilizations is very likely,” replies Li Baoda. “The universe is immensely vast, containing countless trillions of stars and star systems capable of supporting extraordinary forms of life.”
Source: www.brasildefato.com.br
