On this day, 41 years ago, on December 12, 1984 (October 20, the 1984 lunar calendar), American astronomers observed the first planet outside the solar system. On December 12, 1984, American newspapers reported that American astronomers had observed what might be the first planet outside the solar system. Astronomers at the University of Arizona in the United States, when using a four-meter telescope equipped with infrared sensors to observe the heat emitted by distant objects that summer, they repeatedly observed a hot gas planet about the size of Jupiter, the largest planet in the solar system, and a mass of 30 to 80 times its size. The planet orbits the faint star Van Bisbrock 21 light-years away from Earth. According to reports, the distance between the newly discovered planet and Van Bisbrock VIII is roughly equivalent to the distance between Jupiter and the Sun. Astronomers believe that the newly discovered planet has a surface temperature of 1093 degrees Celsius, hotter than any planet in our solar system, but it is too dim and too cold to be a star. They believe there is no doubt that it is a planet rather than a star. Scientists estimate that if it is indeed a planet, then this discovery is a major breakthrough in the long-term exploration of planetary systems outside the solar system, and also provides the first direct evidence of the possible existence of life beyond the Earth.