Chapter 1503: Shackleton Crater

Chapter 1538 Shackleton Crater
Because this basin is very large, it has a diameter of 2,000 kilometers and a depth of 12 kilometers. In this case, from a high altitude, it looks like someone deliberately dug a large hole in Antarctica.
Feifei looked at the big hole on the monitor, and he was very happy. After all, what he wanted to see was this Aitken Basin.
‘Dad, now it seems that we can only admire this Ai Te watch basin at such a height. If we fly below, will we not see anything? Feifei thought, since the Aitken Basin is completely dark, their flying saucer spacecraft will not see anything when they fly into this basin.
After hearing Feifei’s words, Zhao Zhongyao said, ‘When it comes to the Aitken Basin, there is really nothing good to see. However, in this basin, there is a relatively large impact crater, which is still relatively beautiful. ’
'what! There is also an impact crater in this basin. What does that impact crater have to do with this basin? Feifei said again.
‘This impact crater has nothing to do with this big basin itself. The Aitken Basin is a very old huge impact crater. It may be more than 3 billion years ago that a huge asteroid collided with the moon.
The impact craters in this basin are relatively young. But when did it happen, we have to probe below to know. Said Zhao Zhongyao.
Feifei heard what his father said, and said, ‘then let’s go and see! I want to know what the impact crater looks like. ’
‘Don’t worry, listen to me about this impact crater! Zhao Zhongyao felt that it would be better to tell his son about this impact crater first. This will allow Feifei to have a general understanding of the impact crater.
‘Okay, let’s listen to Dad’s talk about this impact crater first! At this moment, Feifei looked at his father again and said.
‘Okay, let me tell you about this Antarctic impact crater. The crater is located in the Aitken Basin. The eye-catching impact craters distributed around the ring include Shoemaker Crater, Haworth Crater, De Gerach Crater, Sverdrup Crater, Slater Crater, Stini Crater; and a little further away, located on the eastern half of the moon's front side, are larger craters named after two early Antarctic explorers-Amundsen Crater and Scott Crater.
Shackleton Crater has a diameter of 20.92 kilometers and a depth of about 4.2 kilometers. The moon’s rotation axis is located just a few kilometers from the center of Shackleton Crater. From the earth, only the edge of Shackleton crater located on the rough, rugged high ground can be seen. Its crater wall is slightly protruding from the moon surface, and the outer is slightly corroded by impact, but there is no obvious intertwined crater wall. From a perspective of –90°, the of the outer wall of the crater is about 1.5°.
Since the moon’s orbit and the ecliptic are only inclined by 5°, the interior of the crater is in permanent darkness, but the wall peak of the ring crater is almost continuously exposed to sunlight, and the time exposed to the sun accounts for about the total lunar orbital period. 80-90% of it. The continuously illuminated mountain range is also known as Yongju Peak, which has existed since the 20th century.
The Japanese Moon Goddess probe used the reflection of the pit wall to image the shadow area in the pit. The inside of the crater is composed of a uniform inner wall with a of 30° and a crater bottom with a diameter of 6.6 kilometers. There are a few small craters with a diameter of no more than a few hundred meters.
The bottom of the pit is covered with a layer of concave and convex mound-like structure about 300-400 meters thick, and the height of the central peak is about 200 meters. The permanent darkness keeps the temperature of the bottom of the crater in the Antarctic region constant below 100K. In the case of Shackleton Crater, the average temperature measured is about 90K, while the bottom of the crater is as low as 88K.
Under these conditions, it is estimated that the loss rate of any water ice will be only 10-10 msec. All water molecules arriving here with the comet that accompanies the impact will be frozen at or below the bottom of the pit. The data measured by the Lunar Prospector probe shows that the hydrogen content in the crater is much higher than the general level of the moon surface, which indicates that there may be water ice. However, the albedo at the bottom of the crater is consistent with the back of the moon, which indicates There is no exposed surface ice at the bottom of the pit.
Seen from the earth, the crater is located on the southern edge of the moon, making observations more difficult. Until the appearance of the orbiting spacecraft, no detailed maps of the polar regions and the back of the moon had been surveyed. Shackleton Crater is completely located in a vast, one of the largest known impact craters in the solar system-the Antarctic-Aitken Basin.
The basin is more than 12 kilometers deep, and exploration of it may provide useful information about the interior of the moon. The neutron spectrometer on the Lunar Prospector probe detected high concentrations of hydrogen near the north and south poles of the moon, including Shackleton Crater. At the end of the mission in July 1999, the probe hit near Shoemaker Crater, hoping to detect water molecules in the dust emitted by the impact through telescopes on Earth.
However, no water molecules were detected in the impact, which may indicate that the hydrogen does not exist in the form of hydrates, or that there is no ice at the impact site; or, the impact depth may not be enough and the surface debris layer was not released. A certain amount of water molecules. Judging from the images of the edge of the crater taken by radar and satellites on the earth, its appearance is relatively complete, very much like a young crater that has not been eroded by subsequent impacts.
This may mean that its inner wall is relatively steep, which will cause inconvenience to unmanned probes that land on the moon. In addition, it is possible that the crater formed on its own, and sufficient volatiles have not yet been collected at the bottom of the crater. However, the geological age of the craters around it is quite long and may contain obvious hydrogen in the form of water ice.
Radar research before and after the Lunar Prospector mission showed that the reflection characteristics of the inner wall of Shackleton Crater are similar to those of some craters exposed to sunlight, especially around it, which seems to have a large amount of sputtering covering. This shows that its radar reflection characteristics are the result of rough surfaces, not ice. This is consistent with the situation reflected in previous radar data from the Clementine spacecraft.
But this explanation has not yet achieved unanimous approval in the scientific community. The 13 cm wavelength radar image shows that there is no evidence of water ice in the crater.
This time we went to the Shackleton Crater to explore, to see if there is water ice at the bottom of the crater. Although before, we have conducted a series of explorations of this crater on Earth. But that was an indirect detection after all, not a direct detection. This time, we are going to see the Shackleton crater in person. ’
Looking at Feifei, Zhao Zhongyao talked about this Shackleton impact crater. After hearing this, Feifei was very curious about this impact crater.
‘Dad, let’s go and take a look! Feifei heard what his dad said about the Shackleton impact crater, so he wanted to go and have a look.
‘Okay, let’s go! After Zhao Zhongyao told his son about the Shackleton crater, he drove the flying saucer spacecraft to the Shackleton crater at the center of the South Pole.
Soon, the flying saucer spacecraft flew over the impact crater. The flying saucer spacecraft is now one kilometer above the impact crater. At this height, the overall shape of the Shackleton crater can already be seen.
This is a huge bowl-shaped impact crater. Surrounded by steep mountains, there is a low-lying area in the middle. Because the sun cannot shine on this low-lying area of ​​the impact crater. Therefore, the entire low-lying area has always been in darkness. Now no one knows what's in this low-lying area.
Although the entire Aitken Basin is in darkness. But the edge of Shackleton's impact crater is indeed very bright. Because the edge of the impact crater is towering over the entire Aitken Basin.
Although most of the Aitken Basin is dark. But the surrounding area of ​​the Shackleton impact crater is indeed unusually bright. Because there is sunlight that can shine on these edge peaks.
In this way, from a close perspective, this Shackleton impact crater is really amazing. Because the rest of the entire impact crater is invisible. The only place I can see is the edge of the impact crater. How can it not make people feel amazing.
Because sunlight travels in a straight line in space, there is no scattering phenomenon. So, from the surface of the moon, the Shackleton crater in front of you feels like a phantom in the void. After all, there is darkness all around, only the circle of peaks is bright. It looks like this, of course, is very magical.
‘Dad, this impact crater looks amazing! Feifei looked at the wonder in front of her, and couldn't help marveling.
Tiantian and Qu Yuqian also saw the wonders in front of them. The two of them also stared wide-eyed, looking at the circular impact crater under the spacecraft in surprise. Looking at the circle of bright peaks, both of them felt amazing.
‘Of course, how else would we come to see it! Zhao Zhongyao also looked at the strange scene in front of him with some surprise and said.
‘Then let’s look down now! I really want to know what magical things are in this impact crater. ’
Feifei feels that since this impact crater looks very magical from a high altitude. Will there be many magical things in this impact crater?
‘It’s a wonder, there must be strange things. I also think that there must be something magical in this magical impact crater. Zhao Zhongyao also thought the same as Feifei.
‘Dad, let’s hurry up and take a look inside this crater! Feifei was a little anxious, and wanted to hurry up and take a look inside this impact crater.
Tiantian and Qu Yuqian looked at Zhao Zhongyao after hearing Feifei's words. I want him to quickly drive the UFO spacecraft to see this magical impact crater.
But at this time, Zhao Zhongyao looked at everyone again and said, ‘Don’t worry, let’s land the flying saucer spacecraft on an edge mountain. ’
When Feifei heard it, he didn't understand. He looked at his father and asked, ‘Dad, why do you want to land on the edge of the mountain! Just fly directly into the impact crater. ’
‘We’re going to detect the time when the edge of this impact crater was formed. We need to see if this crater was formed at the same time as the Aitken crater. Still, this crater is a very young crater. ’
Zhao Zhongyao now wants to clarify this question. Although they have explored this crater before, but. At that time, the age of this impact crater was only detected indirectly by launching a detector.
The method at the time was very inaccurate. After all, it is very inconvenient to remotely control detectors on earth. It is difficult for the samples taken with the detector to be universal. They usually collect some rocks from places where the detectors are easier to collect. These rocks may not be the rocks formed when this crater hit the moon. Therefore, we are now going to collect more rocks on the top of the edge peak of this collision and conduct another test. Only in this way can we have more reliable data.
Feifei heard what Dad said, and of course he agreed that Dad would first go to the edge of the Shackleton crater to have a look.
'OK then! Let's go to the top of these mountains to see the scenery first! Feifei said, looking at his father again.
At this time every day, she seemed more happy. She saw that Feifei was unhappy, and said, ‘Brother, it’s great for us to go to the top of the mountain first. There is sunlight on this mountain. It must be more fun than going inside the crater. ’
‘Okay, let’s go to the edge mountain first. After hearing what Tiantian said, Feifei became very interested in these fringe mountains.
Qu Yuqian didn't say anything now. She is the mother of Feifei and Tiantian. She came out to play this time purely to accompany the two children out to play, she never argued with the two children. As long as the two children are willing to play there, she will agree.
Zhao Zhongyao saw that the two children were also willing to go to these fringe mountains first. He also flew the flying saucer spacecraft to the edge of Shackleton's mountain.
Because Zhao Zhongyao was driving a flying saucer spacecraft just now and hovering over a thousand meters above the Shackleton impact crater. Now he only needs to drive the flying saucer spacecraft to land on a peak on the edge of the impact crater.
So, Zhao Zhongyao drove the flying saucer spacecraft to this impact crater. Soon, he was driving in a flying saucer spacecraft and flew over an edge mountain peak.
What Zhao Zhongyao and the others saw from high above was only the appearance of the entire impact crater. I feel that the impact crater is not too big. But when they really flew to the top of a mountain in the impact crater, they felt that the impact crater was also very large.