Xinghai's Suicide Note

In 2187 AD, mankind received a clear signal from an intelligent civilization outside the solar system for the first time. The signal came from a star about 46 light-years away from the solar system. After the content was decrypted, there was only one sentence: "Don't answer us." Later, humans discovered that this message had actually been circulating in the universe for more than 27,000 years. The civilization of sending messages is long dead. But the signal ultimately hides a set of coordinates. There exists a huge artificial structure floating in interstellar space. Humans call it: "Tombstone." Tombstones contain the entire history of a dead civilization. And this civilization left a warning before its demise: "When you start asking why the universe exists, it will start paying attention to you too."