Swiss astrophysicist Michel Mayor and Vietnamese physicist Phan Bao Ngoc are answering questions on the universe and life outside our Mother Earth from Vietnamese science-lovers during an online chat hosted by Tuoi Tre in the coastal city of Quy Nhon.
Mayor, professor emeritus at the University of Geneva's Department of Astronomy and Associate Professor and Doctor Ngoc have received dozens of questions about the mystery around the universe, aliens, UFOs, and extraterrestrial life.
Below are their answers to the local astronomy-lovers’ questions.
* How many universes are there? What are their shapes? Is it possible that there is a universe ‘neighboring’ ours and there are many Earth-like planets there? (pham ke kien, 20, email@example.com)
Prof. Mayor said we are currently only able to study the universe within a range of 13.7 billion light years. If there are other universes beyond this range, people cannot know and get any information about it.
There is currently no evidence of the existence of other universes, so there is little likelihood that a universe ‘neighboring’ ours exists, he added.
* Astronomy is not taught at schools in Vietnam and as a result, most Vietnamese have little knowledge of this science. One bad consequence is that superstition and fortune-telling are now rampant in the country. Fortune-tellers say people’s destiny is determined by stars in the universe. So how are the ‘stars’ of the fortune-tellers different from the stars in astronomy? (tranngochung, 75, firstname.lastname@example.org)
Prof. Mayor said astronomy should be taught at school, adding that teaching the science to children is quite easy. All people have to do is point to the stars in the sky and ask their children what they are. He also suggested that people should familiarize their children with science. He had no idea about the difference between the stars of the fortune-tellers and these in astronomy.
* How can scientist say that life exists outside the Earth? (Nguyen Van Hai, 16, email@example.com)
Assoc Prof. Dr. Ngoc: The main reason for scientists to believe in extraterrestrial life is that there are billions of galaxies in the universe and each galaxy has billions of stars. Each star also has satellites orbiting it. So it is very likely that there is life outside our Solar System.
* You must be very passionate about your field of research. Where does your biggest inspiration come from? Were you a fan of novels by Jules Vernes in your childhood? (dao nguyen khanh, 27, firstname.lastname@example.org) Prof. Mayor said he had read some novels by Vernes. He was also interested in other branches of science when he was a child. He added that he was satisfied with any branch of science at that time. He concluded all branches of science, or even science fiction, are interesting.
* What can we see with our naked eyes when we are outside the Earth’s atmosphere? (nguyen minh dung, 45, email@example.com) According to both professors, astronauts said they saw very dark space and bright stars of the Milky Way.
* How many Earth-like planets are there in the universe? (Le Vu Son, 12, levuson02) Prof. Mayor said that of the 2,000 planets found so far, there are roughly ten planets in the habitable zone. Some of these planets have a similar size to that of the Earth, while others are bigger. But he thinks there are only two planets that may have life.
* Please tell us how people can measure the distance between our Earth and stars that are far away from us? (Hoang Thao, 18, firstname.lastname@example.org)
Assoc Prof. Dr. Ngoc: There are some methods to measure the distance between the Earth and these stars, one of which is the annual parallax.
The annual parallax method is based on the Earth’s orbit around the Sun. Annual parallax is normally measured by observing the position of a star as the Earth moves through its orbit. From the angle subtended at a star by the mean radius of the Earth's orbit around the Sun, we can calculate the distance from the Earth to that star. Another method is spectroscopy.
* Dear Professor Michel Mayor! Does the real history of the universe differ from its history as known by human beings? I wish you good health! (Le Van Tung, 32, email@example.com)
Prof. Mayor said that there are many points of view on the history of the universe in the history of human evolution. The Swiss professor insisted that our current view on the history of the universe is reliable. He added that we can now observe far-off galaxies and even the materials from which these are made of thanks to our modern equipment.