Meet Yan Hongsen, the 11-year-old Chinese boy who wrote 600 lines of code, built a rocket and became known as “Rocket Boy”

In 2024, Yan Hongsen attracted attention for his work on rockets and programming, the boy from Zhejiang, China, was 11 years old at the time, and reports said he had taught himself programming, physics and chemistry while working on his rocket projects.

Media reports referred to Yan as “Rocket Boy” as details of his work gained attention online.

Who Is Yan Hongsen, China’s “Rocket Boy”

The South China Morning Post reported on Yan's rocket projects in July 2024, when he was 11.


According to the report, Yan had developed an interest in rockets at a young age and had taught himself programming, physics and chemistry. His work included building rockets and developing code for their flight-control systems.

Yan Hongsen Wrote More Than 600 Lines of Code

One of the details highlighted in the 2024 reports was Yan's work on flight-control software.

The South China Morning Post reported that Yan had written more than 600 lines of code for the flight-control system of his latest rocket. The code was therefore connected to his later rocket project rather than the first rocket he built.

Other reports likewise described the 600 lines of code as being written for his newer or second rocket.

Yan Started Building His First Rocket in 2022

Yan began building his first homemade solid-fuel rocket in August 2022.

Reports said he spent about 10 months working on the project. He named the rocket “Sen Xing,” and launched it in June 2023.

His First Rocket Launch Ended in a Crash

The launch of Sen Xing in June 2023 did not go as planned.

According to reports, the rocket crashed during the launch after a problem with its parachute. The incident was associated with the first rocket project, while the 600-plus lines of flight-control code were reported in connection with Yan's later rocket.

Yan’s Interest in Rockets Began When He Was Young

Yan's interest in rockets began before he started building them himself.

The South China Morning Post reported that his father said Yan became interested in rockets after watching a rocket launch when he was four years old. By 2024, his projects had progressed from building his first rocket to working on flight-control code for a later one.

What Reports Say About Yan Hongsen

The 2024 reports documented the work of an 11-year-old from Zhejiang who had taught himself programming, physics and chemistry and was building rockets.

His first rocket, Sen Xing, was started in August 2022 and launched in June 2023 after about 10 months of work. The launch ended in a crash following a parachute problem.

By July 2024, Yan had also written more than 600 lines of code for the flight-control system of his latest rocket, according to the South China Morning Post.