合理质疑不是楼主这种态度和口气，而是自己有了一定了解和学习之后，提出疑问。我自己之前的印象，因为火星是和地球最类似的行星，所以探索火星的一个重要原因是和地球类比，寻找生命起源。再就是，火星是走出地球最容易到达的星球，而人类对宇宙的探索与好奇，从来没有停止过。按照楼主的逻辑，中世纪的人也根本无需用生命捍卫日心说，和生活有一毛钱关系？

随便问了一下，网上给出的为什么要去火星，提出了下面几点答案，供参考：

There are many reasons to explore Mars, including:

• Search for life
• Mars is the most similar planet to Earth in our solar system, and it's one of the only other places where life may have existed. Finding life on Mars would change our understanding of our place in the universe. 
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• Learn about Earth's history
• What we learn about Mars can help us understand Earth's past and future. For example, Mars' history of water can help us understand how life could have survived on Earth. 
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• Develop new technologies
• Space exploration has led to the creation of many technologies, including GPS, medical diagnostic tools, wireless technology, and camera phones. 
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• Prepare for future human exploration
• Exploring Mars can help us prepare for future human exploration by helping us understand how to keep astronauts safe in the harsh Martian environment. 
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• Demonstrate political and economic leadership
• Going to Mars can demonstrate political and economic leadership. 
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• Understand the formation of our solar system
• Studying Mars can help us understand how planets form and evolve, and the distribution of life in the universe. 
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• Potential for mining
• Mars may contain economically mineable amounts of lithium, cobalt, nickel, copper, zinc, and other materials. 
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