Professor Jilin Zhou from the School of Astronomy & Space Science of Nanjing University delivered a lecture titled “From Wandering Earth to Finding Another Home: Starting from 2019’s Nobel Prize in Physics” in Guosheng Lecture Hall of Kuang Yaming Honors School in the afternoon of October 27.

Professor Zhou started from 2019’s Nobel Prize in physics and asked why we need to find another earth. By listing the Nobel Prize in physics that were awarded to the field of astrophysics since 1967, he pointed out that astrophysics stood out in the last ten years.

Professor argued that many scientific and technological breakthroughs originally derived from the evolution of the fundamental physics. Both black holes and gravitational waves came from humans’ knowledge of the nature, humans’ civilization development and humans’ understanding of themselves.

He mentioned that the movie Wandering Earth provided some insights and made people think about the earth they are living on. Is humans’ existence on the earth something bound to happen or a coincidence? Thanks to its location in the solar system, the earth boasts pleasant temperature and liquid water. However, are there other habitable planets?

There are fewer resources on the earth and its environment has been greatly damaged. The sun will die one day. As hydrogen burning and helium burning go on inside the sun, it will collapse, produce more heat, expand into a red giant, engulf close planets and destroy the habitable environment of the earth.

Professor Zhou stated that finding another earth is important because it’s closely related to questions about the origin of life, extraterrestrial civilizations and humans’ fate.

To answer these questions, scientists need to find planets and figure out whether they are habitable.

He proceeded to talk about why it is difficult to find planets. Planets are very dark and the level of their radiation is pretty low compared to stars, which makes them hard to detect. Scientists mainly take advantage of the two-body problem and the transit of celestial bodies to detect planets indirectly. However, the Kepler Space Telescope in the United States has failed to find planets that are similar to the earth in both radius and movement patterns up till now.

In addition, the detection of exoplanets has become a hot topic. The professor stated that The Three Body Problem, a popular sci-fi novel series, is not totally fictional. Some phenomena mentioned in the book, like Proxima Centauri, do exist in reality. Then, he described what sort of planets are habitable.

At the end of the lecture, Professor Zhou talked about the work of Nanjing University’s research expedition team. The team mainly carries out research in Antarctica and China’s Lenghu town.

The vivid lecture broadened the students’ minds and kindled their interest in celestial body research.