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Scientists are considering the possibility of sending humans to Mars in the coming decades. Although there have been successful manned missions to the Moon in the 1960s and 1970s, Mars is 150 times further away from Earth than the Moon is. Thus the project of sending humans to Mars would require solving an array of problems the Moon missions did not have to face. One problem is that a round-trip to Mars and back is likely to take at least two years. The trip to the Moon lasted only a few days, and it was easy to bring enough supplies of food, water, and oxygen; but the cargo capacity of space vehicles is too limited to put on board the food, water, and oxygen required by a crew for a period of two years. Without those essentials, though, a Mars mission is impossible. A second problem is that astronauts on the Mars mission would be in the zero-gravity environment of space for many months at a time. Spending a long time in the zero-gravity environment has negative effects on the human body, such as decreased muscle mass and lower bone density. Over the course of a two-year mission, the effects would be so severe, they would make it impossible for humans to make the trip without experiencing grave medical problems. Finally, astronauts on a mission to Mars would be exposed to dangerous levels of space radiation, much of which comes in the form of charged particles emitted by the Sun. Earth’s magnetic field, which normally protects us from dangerous solar radiation, would not be able to protect a spaceship traveling in interplanetary space. Constructing a shield that would protect the whole spaceship from space radiation is at present impossible because it would add too much weight to the ship.
The reading and lecture discusses about the solution to the problems that would arise while sending humans to mars.The author of the reading states three main problems involved. The lecturer challenges the claims made by the author.
To begin with, the author argues that it is not plausible to carry the necessary survival items in the cargo space for two years. this specific argument is challenged by the lecturer. She claims that astronauts can survive two years in mars by the hydroponics technique where the crops can be grown and also they provide clean water for drinking. Additionally, hydroponics method provide oxygen for breathing.
Secondly, decreased muscle mass and reduced bone density that can occur among the astronauts because of the zero gravity environment on mars.The lecturer rebuts this point by stating that the astronauts can do exercise and have some vitamin supplements to prevent the aforesaid health problem.
Thirdly, the travelers will be exposed to the dangerous levels of radiation on mars. In contrast, the lecturer posits that radiation level will be harmful only during certain levels and a shield that covers the main parts will be beneficial for preventing the radiation effects.
