As technology advances, we are beginning to realize our humble presence in the universe. It’s highly likely that we are just one of many civilizations existing in the galaxy.
The Possibility of Extraterrestrial Life
The existence of life beyond Earth has always been a subject that fuels human imagination. We constantly wonder whether there are other intelligent life forms in the cosmos and if we can ever make contact with them.
Regardless of the existence of extraterrestrial civilizations, the exploration of the universe and the pursuit of the mysteries of life will continue to propel us forward and drive the advancement of science and technology. Image: Zhihu
In recent decades, human confidence in the existence of extraterrestrial civilizations has grown, particularly with the advancement of scientific technology. We’ve discovered a vast number of Earth-like planets, providing more room for the potential existence of extraterrestrial life.
Recent research indicates that there are at least tens of billions of Sun-like stars in our Milky Way galaxy, and each of these stars may have planets orbiting them. This discovery has made “Earth-like planets” – those with similar size, mass, and distance from their host stars as Earth is from the Sun – more common. Such planets are predicted to have conditions suitable for life.
For example, the space telescope Kepler identified a planet known as Kepler-452b, which shares a similar size and orbit with Earth. This planet falls within the habitable zone, where temperature and the presence of water are conducive to life.
Another planet, Kepler-186f, also resides in a potentially habitable zone, raising hope for the existence of life. These findings suggest that Earth-like conditions for life might be more widespread than previously thought.
In harsh environments, such as deep-sea hydrothermal vents and polar ice caps, scientists have discovered microorganisms capable of surviving and reproducing under extreme conditions. This underscores the adaptability of life to various environmental conditions, expanding the search for extraterrestrial life beyond Earth-like environments.
Although there is no conclusive evidence of the existence of extraterrestrial civilizations, these discoveries and explorations offer new hope for their existence. Humanity is currently adjusting astronomical technology to detect signs of extraterrestrial life, such as biological signatures. Additionally, scientists are working to identify environmental indicators on other planets, such as atmospheric composition and temperature, to determine the suitability for life.
While the existence of intelligent extraterrestrial life in the universe remains uncertain, the discovery of Earth-like planets and the existence of extreme life forms on Earth suggest an increasing possibility of extraterrestrial life.
The Number of Extraterrestrial Civilizations in the Galaxy
Extraterrestrial civilizations have always been a part of humanity’s cosmic exploration dreams. Scientists have estimated the number of extraterrestrial civilizations in the galaxy through various methods and speculations. According to their research, there are approximately 36 such civilizations.
Scientists use the “Drake Equation” to estimate this number. The Drake Equation was proposed by astrophysicist Frank Drake in 1961 to calculate the number of extraterrestrial civilizations that could exist in galaxies similar to the Milky Way within our universe. The formula considers factors like star formation rate, planet formation rate, the proportion of habitable planets, the origin of life, and more.
Scientists also extrapolate this number based on findings in the fields of astrobiology and astronomy. They have discovered that there are billions of stars in the Milky Way, many of which could host planets. Furthermore, experimental findings of extraterrestrial life suggest that there are environments in the universe conducive to life. All of these pieces of information support the existence of extraterrestrial civilizations.
Efforts to search for extraterrestrial civilizations in the cosmos have begun and have achieved some encouraging progress. For instance, we can use radio telescopes to monitor signals emanating from deep space and search for clues of extraterrestrial intelligence. Simultaneously, some scientists are exploring planets in other galaxies where conditions might allow for the existence and development of life. Image: Zhihu
While scientists estimate around 36 extraterrestrial civilizations in the Milky Way, there is currently no direct evidence to prove this. To date, humans have not received any signals from extraterrestrial civilizations nor discovered any concrete evidence of their existence. Part of this could be attributed to the limitations of our technology and the vastness of the galaxy, making contact with other civilizations relatively challenging.
In the vast universe, most stars have the potential to harbor life, which strengthens our hope for the existence of extraterrestrial civilizations. Image: Zhihu
However, with the continued advancement of science and technology, as well as our deepening understanding of the cosmos, there will be more opportunities in the future to verify the accuracy of the Drake Equation and increase our chances of contact with other civilizations.