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English GeoScience Café No.25

发布日期:Generate:2018-11-12 15:32:57 阅读次数:Reader:[1867]

Total Lunar Eclipse & Mars Opposition
Host: Uqba Ramzan; Text: Zhuang Ying; Photo: Ahmed Mohamed Reda Mansour; Video: Xu Lei; Reviewer: Li Xuerou, Liu Shanhong, Stephen C. McClure
 
About the speaker
Dr. Leonid Zotov is a visiting scientist from Russia. His research field includes but not limited to Earth’s rotation, climate change and its relation. He has published more than 50 articles and conference proceedings, and more than 100 talks at conferences and seminars. He is now an Associate Professor at National Research University Higher School of Economics, Institute of Electronics and Mathematics, and senior scientific researcher at Sternberg Astronomical Institute of Lomonosov Moscow State University (MSU). He is a member of the program of subject Innovation in Colleges and Universities in China.
 
About this English GeoScience Café session
At 19:00, 25th July 2018, Dr. Leonid Zotov attended English GeoScience Café No.25 and spoke about Total Lunar Eclipse & Mars Opposition. At the beginning, the host gave a quick prologue of the session and introduced the speaker. Then Dr. Leonid Zotov started his talk with his memories of childhood and mentioned an event which was the longest lunar eclipse of the century and the mars opposition simultaneously. He then outlined ten parts of his presentation as follows:
(1) The old story about the moon in China & Europe;
(2) The Lunar Crater & the origin of the Moon;
(3) The Different Phases of the Moon, Lunar period, & Lunar Libration ;
(4) Lunar Eclipse & Total Lunar Eclipse of 27th July 2018;
(5) Moon Orbit Inclination & it’s 18.6 Years Precession;
(6) The Philosophical idea of space explanation (Early Age);
(7) Future Moon Exploration;
(8) The opposition of Mars and 27th July 2018 Mars opposition;
(9) Martian Topography;
(10) NASA’s Journey to Mars: Curiosity rover & Insight Mission
Fig. 1 A moment of Dr. Leonid Zotov’s informative presentation.
 
1. The old story about the moon in China & Europe:
At the beginning of the lecture, Dr. Leonid Zotov showed some of the ancient images. Each of the images represents a story of moon from old China and Europe.
Fig.2 An existing story about the moon in China.
 
Fig.3: An existing story about the moon in Europe.
 
2. The lunar crater & the origin of the Moon:
According to Dr. Leonid Zotov, after observed the moon by using a telescope, there were 13 lunar craters found as shown in Fig.4 (1). The most prominent craters among all the lunar craters named Copernicus and Tycho.
Fig. 4 Giovanni Battista Riccioli (1598-1671) named all 13 lunar craters.
 
Then Dr. Leonid Zotov talked about the origin of the Moon. According to the study, a Mars-sized body struck the Earth about 5 billion years ago, making a debris ring that eventually collected into a single natural satellite of the earth, the Moon, as shown in Fig.5, but there were a number of variations on this giant-impact hypothesis, as well as alternate explanations, and research into how the Moon came to be continuing.
Fig. 5 Origin of the Moon
 
 
3. Different phases of the Moon, Lunar period, & Lunar libration:
Leonid said, the Moon’s phases were the different ways looked from Earth for a month. According to modern cosmology, there were 8 major phases that the Moon went through as shown in Fig.6 (2 and 3).
Fig. 6 Different phases of the Moon & Lunar period
 
The Lunar Sidereal Period is the time when the Moon completes one orbit around the Earth with respect to the stars, also called the “Sidereal Month”. There are two well-known lunar periods called Lunar Sidereal & Synodic Periods as shown in Fig.6(4).
According to Astrology, lunar libration is distinct from the slight changes in the Moon's apparent size viewed from Earth. Although this appearance can also be described as an oscillating motion, it is caused by actual changes in the physical distance of the Moon because of its elliptic orbit around the earth.
Fig. 7 Lunar Libration, Apogee & perigee.
 
4.Lunar Eclipse & Total Lunar Eclipse of 27th July 2018:
A lunar eclipse occurs when the Moon passes directly behind Earth and into its shadow. Here Dr. Leonid Zotov also talked about the total lunar eclipse that would happen on the next Friday night after that.
 
5.Moon Orbit Inclination & it’s 18.6 Years Precession:
Why we can’t see an eclipse every month? Dr. Leonid Zotov provided a detailed explanation which is best considered in terms of the paths of the sun and Moon on the celestial sphere, as shown in the Fig.8.
Fig. 8 Apparent paths of the Sun and Moon on the celestial sphere.
 
6.The Philosophical idea of space explanation (Early Age):
 Dr. Leonid Zotov introduced Nikolay Fedorov (1829-1903) and Constantin Tsiolkovsky (1857-1953), basically two of the greatest Russian philosopher but recognized as the founder of space research because of their ingenious ideas about space exploration.
Fig. 9 Nikolay Fedorov (1829-1903) & Constantin Tsiolkovsky (1857-1953)
 
7.Future Moon Exploration:
According to Dr. Leonid Zotov, the motives of the future exploration might be different by considering different country and time nearly 50 years after the Apollo 11 landed on the moon. Space scientist wanted to make a lunar space station that people could come and rest a bit when we travel to Mars.
Fig. 10 Lunar Space Station.
 
8.The opposition of Mars and 27th July 2018 Mars opposition:
Dr. Leonid Zotov then shared an interesting thing, “The sun, the Earth, and the planet Mars will line up for a once-in-two-years treat called ‘Mars in opposition.’ Every 15 or 17 years, opposition occurs within a few weeks of Mars' perihelion (the point in its orbit when it is closest to the sun). It’s a chance to see the red planet in big, bright detail in the night sky.” And this summer, the opposition would occur on July 27, and Mars would reach its closest approach to the Earth on July 31.
 
9.Martian Topography:
Dr. Leonid Zotov introduced some of the topographic features of planet Mars, as follows.
Olympus Mons is a very large shield volcano on the planet Mars. By one measure, it has a height of nearly 26 km. Olympus Mons (21,229m) is about two and a half times Mount Everest’s(8,848m) height above sea level as shown in figures. Leonid explained, “Valles Marineris (Mariner Valley) is a vast canyon system that runs along the Martian equator just east of the Tharsis region. Valles Marineris is 4000 km long and reaches depths of up to 7 km”
 Moreover, “Almost all water on Mars today exists as ice, though it also exists in small quantities as vapor in the atmosphere, and occasionally as low-volume liquid brines in shallow Martian soil, ” said Dr. Leonid Zotov.
 
10. NASA’s Journey to Mars: Curiosity rover & Insight Mission
Dr. Leonid Zotov then enlightened the audience by sharing some photos of NASA’s Journey to Mars. As shown in Fig.11, NASA’s Curiosity rover was walking on the Martian surface.
Fig. 11 Curiosity ROVER, NASA’s Mars Science Laboratory mission (MSL)
 
Dr. Leonid Zotov said, “This year on 5th of May, NASA launched a new mission called Insight Mission and would land on the 26th of November, 2018 on Mars. The objectives of this mission are to place a stationary lander equipped with a seismometer and heat transfer probe on the surface of Mars to give the Red Planet its first thorough checkup since it formed 4.5 billion years ago.”
In the end, Dr. Leonid Zotov expressed his expectations for scientific research on Mars’ interior structure.

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