This astonishing chain of lights zipping across the sky in a perfectly uniform line then suddenly disappearing had residents concerned they might have witnessed a UFO passing by.

Footage filmed by locals in the city of Hangzhou, in China's eastern Zhejiang Province on the night of November 2, show the bright spots ascending further up. As they flew towards the middle of the sky, they lit up one by one from back to front and then disappeared.

Many locals likened the peculiar sight to a UFO sighting.

Others, however, suggested there might be a more plausible explanation.

Keen astronomy enthusiasts claimed the train of lights was likely the Starlink satellites of Tesla owner Elon Musk's SpaceX company making their way to Earth's lower orbit.

According to SpaceX, the Starlink satellites can be seen from Earth when sunlight reflects off their chassis. While the company acknowledges that any satellite can be visible at night when illuminated by the sun, they have made revisions to newer generations of Starlink satellites to reduce their brightness.

It is reported that from 2019 to 2024, SpaceX has planned to build a 'star chain' network consisting of about 12,000 satellites in space to provide Internet services. The firm said 1,584 of those will be deployed in low-Earth orbit, some 340 miles above ground.

Because the low-Earth orbit is relatively close, the satellites can be seen directly with the naked eye under certain circumstances when the weather is clear.

According to SpaceX's plan, the number of Starlink satellites will continue to increase, and the ultimate goal is to launch 42,000 satellites into Earth's low-earth orbit, making it among the most ambitious satellite launch plans in history.

One of the most important functions of Starlink is to provide communication, which can realise calls and networks without base stations, improving any delay and other data transfer. Many astronomers, however, have expressed concerns about the thousands of Starlink units, worrying they could greatly impact scientific observations.