On January 2, 2004 (December 11, 2003 in the lunar calendar), humans conducted the first sampling from the nucleus of a comet. On January 2, 2004, the U.S. space probe "Stardust" encountered Comet Wilder 2 and used a special instrument to extract material from the comet's core. This was the first exploration activity for humans to sample samples from the comet's core. The picture shows the situation where the "Stardust" spacecraft collects material emitted from the comet core. On February 7, 1999, the United States launched the "Stardust" spacecraft. The main purpose of this launch is to sample and detect Comet Wilder 2 and also collect interstellar dust. The first orbital period of the "Stardust" spacecraft orbiting the sun was two years. From February to May 2000, the "Stardust" spacecraft collected interstellar dust for the first time. These dust were particles newly entered the solar system from interstellar space. It is of great significance to studying the origin of the universe. Dust is the main form of heavy elements that make up the Milky Way. The total collection time for dust particles is about two years. After the collection of dust particles is completed, four years are used to collect comet nuclear samples. On January 2, 2004, the United States '"Stardust" spacecraft will encounter Comet Wilder 2, use special instruments to extract material from the comet's core, and return it to Earth for research. This is the first time that humans have sampled and returned from a comet's core. Space exploration activities. On February 21, the spacecraft moved away from Comet Wilder 2 and returned to Earth on January 15, 2006. A comet is a small, fragile, irregularly shaped object. Although comets are large and can be hundreds of millions of kilometers long, they have various shapes and generally extend away from the sun. The closer they are to the sun, the longer the tail becomes. However, their mass is pitifully small. Even the mass of large comets is less than one-thousandth of the Earth. Comets are the oldest and most primitive objects in the solar system, and they preserve the earliest records of primitive nebula material; comets bring volatile light elements to planets and play an important role in the formation of planet oceans and atmospheres. Direct sampling of Comet Wilder 2 through the "Stardust" spacecraft is conducive to direct testing of solid matter formed outside the solar system. This event has very important historical significance in astronomy.