The possibility of sending human being to mars

The reading passage and the lecture are both about the possibility of sending human being to mars. The author of the reading claims that there are several problems regards sending humans to mars. The lecturer challenges the claims made by the author. She is of the opinion that this trip would definitely be a challenging one but scientists have proposed solutions to these problems. To begin with, the author argues that it will take too long to reach mars and then get back, approximately two years. The article mentions that the space craft has a limited space for storing food, water, and oxygen; so, it is unlikely for this limited supply to be able to provides astronauts in period of two years. This point is challenged by the lecturer. She states that they can use hydroponics. Hydroponics is a technique for growing plants without the need of soil and it requires a little space. Astronauts can cultivate their own food crops in space craft by using this technique. Additionally, she says these plants can recycle waste water and release it as clean water vapor which can be collected as drinking water, and also, like any other plants they will absorb carbon dioxide and release oxygen. Secondly, the writer asserts that during this trip astronauts would be in a zero-gravity condition and it will adversely affect their health. In the article, it is said that spending several months in such an environment causes a decrease in the muscle mass of human body and will lower its bones density. The lecturer, however, rebuts this by mentioning that there are already several space stations orbiting the earth and there are a bunch of astronauts who are living there for span of months in zero-gravity. She elaborates of this by bringing up the point that we have several techniques to safely live in zero-gravity such as regular exercise and taking vitamins and mineral like calcium which will prevent decrease in muscle mass and bone density, respectively. Finally, the author posits that astronauts would be exposed to dangerous solar radiation. Moreover, it is stated in the article that it is not practical to shield the whole spaceship against this danger for it makes the ship too heavy. In contrast the lecturer believes that this solar radiation will not always be at a dangerous level and sun only emits dangerous amount of radiation occasionally. She notes that for avoiding this threat the spaceship could be provided with special monitoring equipment for identifying dangerous radiation and a small shelter which could shield astronauts for this danger but does not add too much weight to the ship. She added that when this kind of instruments detect dangerous radiation astronauts can use the small shelter to be safe against it.