From “small balls of light” to speeding “cloud-like” objects, residents of Beijing and several regions in northern China reported sighting unidentified flying objects in the sky Sunday night, igniting widespread speculation on social media.

Experts have attributed the phenomenon to SpaceX’s new rocket launch for its Starlink satellites.

On the microblogging platform Weibo, witnesses shared multiple accounts and videos of what they believed were unidentified flying objects.

One observer described them as “light clusters of mist” with a halo, noting that they gradually transformed into three smaller orbs of light.

Another observer stated that the luminous object, described as three distinct light sources arranged in an “isosceles triangle,” stood out vividly in the exceptionally clear and cloudless sky that night in Beijing. A third emphasized its high speed, noting how it appeared in a very short time.

The phenomenon quickly gained momentum on Weibo, and was the second-highest trending topic on Monday, with 180 million views. Netizens offered an array of speculations, ranging from the possibility of extraterrestrial visitors to conjectures about foreign aircraft.

Zhu Jin, a researcher at the Beijing Planetarium and editor-in-chief of the Amateur Astronomer magazine, told local media that the phenomenon was a direct result of a Starlink satellite rocket launched by the American space technology company. Zhu said the rocket was in the process of undergoing passivation as it flew over north China.

According to Zhu, passivation is the procedure in which a rocket disposes of unused fuel. This step is taken to prevent potential threats to the satellite’s operation or collisions with it. During the final stage, the rocket vents remaining fuel and high-pressure gas, allowing the batteries to short-circuit, thereby eliminating any risk of self-explosion.

SpaceX, founded by Elon Musk, conducted two Starlink launch missions on Jan. 14, according to its website. At 0:59 a.m. local time (4:59 p.m. China Standard Time), a Falcon 9 rocket launched 22 Starlink satellites into near-Earth orbit from California. Subsequently, at 8:52 p.m. local time (12:52 p.m. CST the following day), another rocket launched 23 Starlink satellites from a spaceport in Florida.

“It’s obviously a man-made object, not a natural phenomenon,” Dong Zhichuan, head of science popularization at the Nanjing Institute of Astronomical Optics & Technology of the Chinese Academy of Sciences, told Sixth Tone.

“With advances in the exploration of the universe and the commercialization of near-space launches, we can expect to see more of these unidentified flying objects in the future,” he said.

Similar sightings were also reported in various parts of China last September, when residents in areas around Beijing and the eastern provinces of Shandong and Jiangsu said they saw a halo composed of two beams of light.

Wang Kechao, the head of science popularization at the Purple Mountain Observatory under the Chinese Academy of Sciences, had attributed the phenomenon to contrail clouds formed by spacecraft jet exhaust that reflected sunlight at high altitudes.

Editor: Apurva.

(Header image: A screenshot shows the flying object in the sky, in Beijing, Jan. 13, 2024. From Weibo)