At 11:21 a.m. on May 7, 2024, the Long March 6C carrier rocket was successfully launched from China's Taiyuan Satellite Launch Center, sending Neptune-01 and three other satellites into their planned orbits. The mission was a complete success. This launch marks the maiden flight of the Long March 6C carrier rocket, signifying a new addition to the Long March rocket family. This extension further enriches the lineup of China's new generation of Long March series of launch vehicles, and accelerates the renewal and generation shift of China's active launch vehicles. Both the Long March 6C carrier rocket and the Neptune 01 satellite were developed by the Shanghai Academy of Spaceflight Technology (SAST).

New Youth Rocket

Designed for the Commercial Launch Market and Aimed at Boosting the Development of New Quality Productive Forces

The thriving commercial space launch market has received significant attention, with "Commercial Space" being recognized in the government work report as a "new growth engine" for the first time. This acknowledgment opens up fresh opportunities for the space industry. The Long March 6C carrier rocket, aimed at the future commercial launch market, exemplifies SAST's proactive alignment with national objectives. Its development signifies a proactive stance in embracing evolving productive force dynamics and nurturing strategic emerging sectors, thereby driving the progression of new quality productive forces. This rocket launch initiative underscores SAST's dedication to adapting to the evolving landscape of intensive research and launch requirements under new circumstances. By continually refining scientific research and production management processes, SAST is actively assuming the responsibility to promote the rapid advancement of China's aerospace technology.

The rocket features a single-core and two-stage design. The first stage has a diameter of 3.35 meters and is powered by two liquid oxygen/kerosene engines, each generating 120 tons of thrust. The second stage, with a diameter of 2.9 meters, employs a single liquid oxygen/kerosene engine delivering 18 tons of thrust. The total length of the rocket is about 43 meters, with a takeoff weight of about 215 tons. It has a carrying capacity of about 2.4 tons for a 500 km sun-synchronous orbit and can be equipped with various satellite fairings according to different launch missions.

In response to the robust demand in the domestic commercial launch market, the Long March 6C rocket has embraced the commercial space trend, diligently forging new business strategies to infuse the Long March series with a fresh dynamism. The four satellites launched in this mission were carried out through a commercial "rideshare" launch arrangement facilitated by the Long March 6C rocket via auction—a pioneering step for the public auctioning for launch services by China's Long March series launch vehicles. With the backing of the renowned technical expertise and service-oriented approach of the Long March "national team," the Long March 6C promises its users dependable, adaptable, and economically advantageous launch options, thus becoming a new force for China's Long March rockets to enter the commercial launch market.

"New Technological Upgrade"

Driving the technological renewal and generation shift of the new generation of launch vehicles.

As the latest addition to the next-generation launch vehicles, the Long March 6C not only incorporates the cutting-edge technological advancements of the next-generation launch vehicles, but also represents a significant "cross-generational upgrade" in its capabilities, setting the course for technological development of the next-generation launch vehicles.

"New Technological Upgrade"

Driving the technological renewal and generation shift of the new generation of launch vehicles.

As the latest addition to the next-generation launch vehicles, the Long March 6C not only incorporates the cutting-edge technological advancements of the next-generation launch vehicles, but also represents a significant "cross-generational upgrade" in its capabilities, setting the course for technological development of the next-generation launch vehicles.

During the development phase, the Long March 6C rocket extensively inherited the advanced technologies and products from its predecessors, the Long March 6, Long March 6A, and other next-generation launch vehicles, achieving an impressive productization rate of up to 95%. The team capitalized on a wealth of ground and flight test data from existing models and employed numerical simulation to refine and iterate the design of the Long March 6C rocket. This strategy removed the need for traditional large-scale ground tests during the development of new models like aerodynamic wind tunnels, full-rocket modal analyses, and static section tests, further streamlining the development workflow and cutting costs. The team also used a strategy of de-tasking design and selective product installation to create a "standard rocket" that can adapt to multi-task requirements. This approach not only establishes a foundation for subsequent production in rolling batch and rapid contractual execution but also significantly enhances the rocket's adaptability to different missions and its competitive edge in the market.

This mission marks the maiden flight of the Long March 6C carrier rocket, the 209th flight of the Long March rocket series developed by SAST, and the 520th flight of China's Long March-series launch vehicles.

Neptune-01 is an experimental satellite within the Neptune constellation. This project, which consists of one test satellite along with twelve operational satellites, is committed to creating and managing a low-orbit real-time imaging observation satellite constellation. It aims to provide global, satellite-based real-time imaging services.

Neptune-01 operates in a sun-synchronous orbit at an altitude of 507 kilometers, with a total weight of 239 kilograms. The satellite's primary payload is an X-band Synthetic Aperture Radar (SAR), which employs a concentrated transmission system consisting of "a reflector antenna and a traveling wave tube amplifier", making it a commercial lightweight reflector SAR. Its system sensitivity, along with azimuth and range ambiguities, meets exceptional standards. The satellite supports multiple operational modes, capable of providing high-resolution images for various users. It offers quantitative SAR satellite data for diverse applications, including mapping, land use, disaster reduction, oceanography, forestry, transportation, and water conservancy.