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每日阅读汇总贴http://forum.chasedream.com/GMAT_RC/thread-562296-1-1.html
逻辑姊妹篇：http://forum.chasedream.com/GMAT_CR/thread-580862-1-1.html
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Today, we begin a new series from a book by American writer Edgar Rice Burroughs. The book is called "A Princess of Mars." It is the first book in a series that Mister Burroughs wrote about a man who travels to Mars during the last years of the eighteen hundreds. There, the man meets strange beings and sees strange sights. At first he is a captive, then a warrior, and after many battles, a prince of a royal family.
JOHN CARTER: I am a very old man. How old I do not know. It is possible I am a hundred, maybe more. I cannot tell because I have never aged as other men do.
So far as I can remember, I have always been a man of about thirty. I appear today as I did forty years ago. Yet, I feel that I cannot go on living forever. Someday I will die the real death from which there is no escape. I do not know why I should fear death. I who have died two times and am still alive.
I have never told this story. I know the human mind will not believe what it cannot understand. I cannot explain what happened to me. I can only tell of the ten years my dead body lay undiscovered in an Arizona cave.
My name is John Carter. I am from the state of Virginia. At the close of the Civil War I found myself without a home, without money and without work.
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I decided the best plan was to search for gold in the great deserts of the American Southwest.
I spent almost a year searching for gold with another former soldier, Captain James Powell, also of Virginia. We were extremely lucky. In the winter of eighteen sixty-five we found rocks that held gold.
Powell was trained as a mining engineer. He said we had uncovered over a million dollars worth of gold in only three months. But the work was slow with only two men and not much equipment. So we decided Powell should go to the nearest settlement to seek equipment and men to help us with the work. On March third, eighteen sixty-six, Powell said good-bye. He rode his horse down the mountain toward the valley. I followed his progress for several hours.
The morning Powell left was like all mornings in the deserts of the great Southwest -- clear and beautiful.
Not much later I looked across the valley. I was surprised to see three riders in the same place where I had last seen my friend. After watching for some time, I decided the three riders must be hostile Indians.
Powell, I knew, was well armed and an experienced soldier. But I knew he would need my aid. I found my weapons, placed a saddle on my horse and started as fast as possible down the trail taken by Powell.
I followed as quickly as I could until dark. About nine o'clock the moon became very bright. I had no difficulty following Powell's trail. I soon found the trail left by the three riders following Powell. I knew they were Indians. I was sure they wanted to capture Powell.
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Suddenly I heard shots far ahead of me. I hurried ahead as fast as I could. Soon I came to a small camp. Several hundred Apache Indians were in the center of the camp. I could see Powell on the ground. I did not even think about what to do, I just acted. I pulled out my guns and began shooting.
The Apaches were surprised and fled. I forced my horse into the camp and toward Powell. I reached down and pulled him up on the horse by his belt. I urged the horse to greater speed. The Apaches by now realized that I was alone and quickly began to follow. We were soon in very rough country.
The trail I chose began to rise sharply. It went up and up. I followed the trail for several hundred meters more until I came to the mouth of a large cave.
It was almost morning now. I got off my horse and laid Powell on the ground. I tried to give him water. But it was no use. Powell was dead. I laid his body down and continued to the cave.
I began to explore the cave. I was looking for a safe place to defend myself, or perhaps for a way out. But I became very sleepy. It was a pleasant feeling. My body became extremely heavy. I had trouble moving. Soon I had to lay down against the side of the cave. For some reason I could not move my arms or legs.
I lay facing the opening of the cave. I could see part of the trail that had led me here. And now I could see the Apaches. They had found me. But I could do nothing.
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Within a minute one of them came into the cave. He looked at me, but he came no closer. His eyes grew wide. His mouth opened. He had a look of terror on his face. He looked behind me for moment and then fled.
Suddenly I heard a low noise behind me.
So could the rest of the Apaches. They all turned and fled. The sound became louder. But still I could not move. I could not turn my head to see what was behind me. All day I lay like this. I tried again to rise, and again, but still I could not move. Then I heard a sharp sound. It was like a steel wire breaking. I quickly stood up. My back was against the cave wall.
I looked down. There before me lay my body.
For a few moments, I stood looking at my body. I could not bring myself to touch it. I was very frightened. The sounds of the cave and the sight of my body forced me away. I slowly backed to the opening of the cave.
I turned to look at the Arizona night. I could see a thousand stars. As I stood there I turned my eyes to a large red star. I could not stop looking at it. It was Mars...the red planet...the red god of war. It seemed to pull me near.
Then, for a moment, I closed my eyes. There was an instant of extreme cold and total darkness. Suddenly I was in deep, dreamless, peaceful sleep.
I opened my eyes upon a very strange land. I immediately knew then I was on Mars. Not once did I question this fact. My mind told me I was on Mars as your mind tells you that you are upon Earth. You do not question the fact, nor did I.
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I found myself lying on a bed of yellow colored grass that covered the land for kilometers. The time was near the middle of the day and the sun was shining full upon me. It was warm.
I decided to do a little exploring.? Springing to my feet, I received my first Martian surprise. The effort to stand carried me into the Martian air to the height of about one meter. I landed softly upon the ground, however, without incident.
I found that I must learn to walk all over again. My muscles were used to the gravity of Earth. Mars has less gravity. My attempts to walk resulted in jumps and hops, which took me into the air. I once landed on my face. I soon learned that it took much less effort for me to move on Mars than it did on Earth.
Near me was a small, low wall. Carefully, I made my way to the wall and looked over. It was filled with eggs, some already broken open. Small, green creatures were in them. They looked at me with huge red eyes.
As I watched the fierce-looking creatures, I failed to hear twenty full-grown Martians coming from behind me. They had come without warning. As I turned, I saw them. One was coming at me with a huge spear, with its sharp tip pointed at my heart!
BOB DOUGHTY:This is Bob Doughty. You have been listening to American Stories and our version of "A Princess of Mars." The voice of John Carter was Shep O'Neal. Our program was written for radio, produced and directed by Paul Thompson.
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Mars Bars: Seasonal Markings on Martian Slopes Could Indicate Flowing Water
Newfound features on the Red Planet hint that liquid water may still exist there
By John Matson | August 4, 2011 |7
In the long hunt for water on Mars, researchers may have finally caught sight of flowing liquid.
High-resolution photographs from NASA's Mars Reconnaissance Orbiter (MRO) show dark, transient features on slopes in several midlatitude locations in the southern hemisphere. The features have appeared in Mars's southern spring across multiple years since the probe entered orbit in 2006, grow in length as they extend downhill, and then fade in late summer or early fall. The new features, which carry the purposefully uncontroversial moniker of recurring slope lineae, or RSL, were announced in a study in the August 5 issue of Science.
The cause of the RSL is unknown, but liquid brines just below the surface could well fit the bill. "We're not ruling out any reasonable explanation at this point," says lead study author Alfred McEwen, a planetary scientist at the University of Arizona in Tucson. The researchers have explored nonliquid processes such as rock slides, but McEwen notes that the timing of the surface markings' appearance and growth seems incompatible with dry phenomena. "There may be someone more clever than us that does come up with something," he says.
Until that happens, however, flowing water is a compelling explanation—and one that opens the door to speculation of life in the Martian soil. "This is the most promising place for water [on Mars] in some place that isn't too cold for life as we know it—and for water that is flowing," McEwen says. The southern slopes where the RSL occur are relatively temperate for the Red Planet, with peak temperatures that rise above 0 degrees Celsius in the summer.
Mars has no shortage of water in the form of ice buried below the surface. And planetary scientists think that the Martian landscape had liquid water billions of years ago. Several lines of evidence for more recent or even extant water on Mars have arisen in the past few years, including a controversial claim that NASA's Phoenix lander photographed droplets of water on its own struts in 2008. Phoenix briefly explored the frigid Martian arctic, so any water it may have encountered must have contained salts and chemicals called perchlorates to enable a very low freezing point.
If the slope streaks photographed by MRO, which occur in warmer locales, are indeed caused by water, that liquid would also be salty. "Mars is just a very salty place," McEwen says. "Any water that flows at the surface or subsurface gets salty." Brines of magnesium chloride, sodium chloride, calcium chloride or iron sulfates all have freezing points that match the MRO observations.
A spectrometer on board MRO was unable to identify the spectral signature of water from the RSL regions, so McEwen and his colleagues suspect that the ground itself is dry and that any liquid flows occur just below the surface.
James Head, a planetary scientist at Brown University who did not contribute to the new study, notes that the question of whether changing surface features on Mars are associated with water or watery brines has beleaguered planetary science for decades. The new discovery, he says, "brings us much closer to understanding the role of such liquids in shaping Mars, even in the current environment."
The potential signature of liquid water may have gone undetected in the orbiter's voluminous catalogue of data and imagery had it not been for the work of a University of Arizona undergraduate. Lujendra Ojha was working to identify changes in images taken by MRO of the same locations at different times when he noticed the transient markings on southern slopes.
"We had them hiding in our images for years without our noticing them," McEwen says. "It's hard to appreciate their significance until you see the images separated by a large amount of time." |
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