China News Service, Beijing, December 20th (Reporter Shangguan Yun) As an terrestrial planet in the solar system, Mars has always attracted much attention.
As "research found that Mars once had a 300-meter-deep ocean" appeared on the hot search, this planet once again attracted the attention of astronomy enthusiasts.
Many people are very interested in Mars.
Some people also asked this question: Are there four seasons on Mars?
What is its climate like?
Data map: China National Space Administration announced on June 29 the images of Mars recently taken by the Tianwen-1 probe.
The picture shows the landform image of the western part of the Grand Canyon of the Mariners taken by the camera. The Grand Canyon of the Mariners extends over 4,000 kilometers from east to west, 150 kilometers to 700 kilometers wide from north to south, and can reach a depth of 7 kilometers.
Photo provided by China News Agency, National Astronomical Observatory of Chinese Academy of Sciences
Zheng Jie, an assistant researcher at the National Astronomical Observatories of the Chinese Academy of Sciences, said that there are also "four seasons" changes on Mars caused by changes in the point of direct sunlight.
However, the environment on Mars is quite harsh.
What are terrestrial planets?
According to data, Mars is a terrestrial planet located in the habitable zone of the solar system. It was called "Yinghuo" in ancient China.
Zheng Jie introduced that the terrestrial planets in the solar system, also known as rocky planets, include Mercury, Venus, Earth and Mars.
To put it simply, their common feature is that they are all planets made of rock as the main material.
Speaking of being similar to the Earth, in terms of size, Venus is actually the closest to the Earth and has an atmosphere, but the composition of the atmosphere of Venus is very different from that of the Earth, and Venus is famous for rotating in the opposite direction to all other planets.
Judging from other conditions, Mars is the most similar to the earth. The rotation of Mars is equivalent to 1.03 days of the earth, and the eclipse angle of Mars is about 24°, which is also close to the earth.
On March 26, 2021, the China National Space Administration released two profile images of the southern and northern hemispheres of Mars taken by the Tianwen-1 probe.
In the image, Mars is in the shape of a "crescent moon" with clear surface textures.
Photo courtesy of the National Space Administration
However, the climate and environment of Mars is equivalent to the desert area of the earth, which is very harsh compared to life on earth.
Mars has a very thin atmosphere, which is not enough to provide the environment needed for the development of life.
Are there four seasons on Mars?
Interestingly, since the ecliptic angle of Mars is about 24°, and Mars is not too far from the sun, there are also "four seasons" changes caused by changes in the point of direct sunlight.
Zheng Jie said that compared with the earth, the "four seasons" of Mars are also divided according to the migration of the position of the sun's direct rays. Of course, this refers to the "four seasons" in the mid-latitude regions. The division of seasons is not the same.
"Its summer and winter are usually referred to the seasons in the northern hemisphere." He mentioned that because the orbit of Mars is outside the earth (the so-called outer planet), the year of Mars is much longer than that of the earth, which is equivalent to about 1.9 years. earth year.
In addition, the orbit of Mars is more "flat" than that of the earth, so the length of its "seasons" is very uneven, and "spring and summer" are about 1/3 longer than "autumn and winter".
And the difference between different seasons is not big, mainly due to the difference in temperature.
In terms of distance, the moon, Venus, and Mars are relatively close to the earth.
But since humans observed Mars through telescopes and learned that Mars is also a planet, the longing for Mars immigration seems to have continued.
Unfortunately, so far, humans have not found traces of life on Mars.
So slowly, human beings changed from fantasizing about Martians visiting the earth, to earthlings visiting Mars.
Data map: Coloring rendering of the first Mars image taken by Tianwen-1.
Photo courtesy of the National Space Administration
This is also reflected in film and television dramas.
Zheng Jie gave an example. The movie "The Martian" tells the story of astronauts trapped on Mars. In the movie, the astronauts also planted potatoes on Mars, realizing the ecological chain of human beings on alien planets.
What are the celestial phenomena associated with Mars?
Mars is no stranger to astronomers.
For example, the astronomical phenomenon of "Mars and the moon" is quite well-known. According to some data, this refers to the astronomical phenomenon that occurs when Mars and the moon move to the same celestial longitude. At this time, the scene of Mars and the moon can be seen on the earth.
Zheng Jie introduced that from the earth, Mars is very bright in the night sky, and the brightest time is close to -3 magnitude, which is very suitable for observation. Moreover, Mars is close to the earth, and when weather conditions permit, it can be viewed with a small astronomical telescope.
"When Mars opposes the sun, the brightness of Mars will reach the brightest level, and Mars opposes the sun about once every 780 days." He said that there are many astronomical beauties in the celestial phenomena related to Mars.
For example, the main celestial phenomena that can be seen on Mars are when Mars is close to other planets or the moon. For example, the "two stars with the moon" that once appeared in the night sky looks like a cute smiling face, which has attracted many people's attention.
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