Faced with the vast and boundless universe, humanity has always been driven by endless curiosity and a desire for exploration. From ancient times to the present day, we have continuously invented and improved observational tools in an effort to unveil the mysteries of the cosmos.

China's Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) plays a pivotal role in this journey of exploration, providing a brand-new perspective and massive data support for humanity's understanding of the universe.

01

Ushering in a New Era of Spectral Surveys

The birth of LAMOST marked a major breakthrough in Chinese astronomy, with its key innovation being an active optics system pioneered in China. In the 1990s, astronomers Su Dingqiang and others proposed a mirror splicing and deformation technology. This allowed for tracking 4,000 celestial objects simultaneously merely by rotating the reflector, even with the telescope tube fixed in place.

When LAMOST begins observation, its reflecting mirror MA, composed of 24 hexagonal sub-mirrors, rotates in real-time to track the target sky area. Actuators beneath the mirrors push and pull, inducing micron-level deformations in the mirror surface, which accurately reflects light from the target area onto the spherical primary mirror MB, composed of 37 hexagonal spherical sub-mirrors. MB then further reflects the light path to the focal plane.

The focal plane consists of 4,000 optical fiber positioning units, each connected to an optical fiber. The positioning system can precisely align the 4,000 fibers on the focal plane according to star catalog positions within minutes, ultimately transmitting the light through the fibers to the 16 spectrographs below, each with 250 channels. This unprecedented technical design made LAMOST the unparalleled king of spectroscopy, capable of observing 4,000 celestial objects at once, truly achieving "a glimpse at a thousand stars."

LAMOST boasts the largest telescope focal plane in the world, enabling simultaneous observation of multiple celestial objects. Its suite of 16 spectrographs also forms the world's largest spectrograph cluster, significantly enhancing spectral acquisition efficiency. Furthermore, its application of active optics technology allows it to apply force to deform the mirror surface in real-time based on the incident angle of the celestial light, correcting for spherical aberration and thus obtaining clearer observational images. These advanced technologies made it possible for LAMOST to acquire vast amounts of celestial spectral data in a short time, laying a solid foundation for subsequent astronomical research.

02

The Development Journey and Scientific Contributions of LAMOST

In April 1993, a research team led by astronomers Wang Shouguan and Su Dingqiang proposed the LAMOST project. After years of meticulous preparation and arduous construction, LAMOST was officially completed in October 2008, installed at the Xinglong Observatory of the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC) on Lianyingzhai in Xinglong County, Hebei Province. It entered the testing and commissioning phase in 2009 and was officially named the "Guoshoujing Telescope" on April 17, 2010. This name not only pays homage to the ancient Chinese astronomer Guo Shoujing but also symbolizes the telescope's important status in modern astronomical research. Its creation embodies the wisdom and hard work of countless astronomers, marking a new height for China in the field of astronomical observation.

The completion of LAMOST opened a new era of large-scale spectral surveys. Prior to this, international spectral survey projects like Australia's 2dFGRS and the American SDSS existed, but LAMOST surpassed them in scale and technology, pioneering internationally the large-scale spectral survey capable of observing thousands of celestial objects simultaneously. As of March 2024, LAMOST has released over 25 million spectra, providing immense data resources for global astronomical research and promoting rapid development across multiple astronomical fields.

By observing vast numbers of stars, LAMOST has helped astronomers better understand the shape, size, and stellar distribution of the Milky Way. Researchers using its data have discovered new structures and features within our galaxy, providing crucial clues for in-depth study of its formation and evolution. For instance, refined understanding of the Milky Way's spiral arm structure and new discoveries about stellar distribution in the galactic halo have deepened our comprehension of the galaxy's overall architecture.

LAMOST has provided rich spectroscopic information for stellar physics research, enabling scientists to delve into stellar physical properties such as temperature, pressure, and chemical composition. Based on its spectral data, researchers discovered a star with the highest known europium abundance, a finding that provides a new sample for studying stellar elemental abundances and evolution processes, helping to refine theories of stellar evolution.

In the search for special celestial objects, LAMOST has played a crucial role. In 2019, Chinese scientists using LAMOST discovered a stellar-mass black hole, the most massive of its kind known at the time. This discovery challenged conventional understanding of stellar-mass black hole formation, broke through the "forbidden zone" of existing stellar evolution theories, and is expected to drive innovation in theories of stellar evolution and black hole formation. Furthermore, LAMOST continues to contribute significantly to the search for other special objects like supernova remnants and gravitational wave sources, offering more possibilities for humanity to explore the universe's mysteries.

As an outstanding representative of China's astronomical observation capabilities, LAMOST testifies to the rapid development of China's journey in exploring the universe. It showcases the relentless pursuit of excellence and the spirit of innovation among Chinese astronomers. These telescopes are not merely tools for exploration but also symbols of human wisdom and courage. It is believed that in the future, with the continued operation of LAMOST and the deployment of more advanced astronomical equipment, we will unveil further mysteries of the cosmos, advancing ever deeper into the universe's expanse and writing a new chapter in humanity's exploration of space.