In a study examining whether terrestrial bacteria could survive on Mars, scientists from Princeton University, the Kennedy Space Center, and Michigan State University, exposed a bacterium, originally isolated from Siberian permafrost here on Earth, to harsh conditions like those on Mars -- low temperatures and atmospheric pressures, and extreme dryness and ultraviolet irradiation flux. Though certain terrestrial microbes might pose a significant contamination threat on Mars, the researchers reported their bacterium could not survive the UV levels typically found on the martian surface. Another article describes exposure of Arctic bacteria to simulated martian conditions, including UV irradiation equivalent to about 80 days on the surface of Mars, freeze-thaw cycles, low pressure, and comparable atmospheric gas composition. In the report, scientists from the University of Aarhus in Denmark say that even a 2-centimeter layer of dust provided significant protection to bacteria, and that they were better able to survive at even greater depths. Bacterial DNA and proteins were more resistant to destruction than the bacteria themselves. So it appears that all an Earth microbe would have to do to survive on Mars would be to dig in for the duration.
This article was very interesting and well written. It presented the findings of why the Arthur believed why alien life was on earth as well as how living things from earth would be able to exist on other plants in a logically and simply way making it easy for the reader to understand what is being described in the article.
http://www.macroevolution.net/weird-alien-life.html
In this review, I felt that Ryan did a admirable job in summing up the key points of the article. Scientific studies are often complex, even in articles meant for the general public, and thus it can be difficult to break down the ideas to just the bare minimum. However, I felt like I understood the basics when I read Ryan’s review. I also thought that Ryan did a good job in explaining the experiments they used in order to test whether or not microbes from Earth could survive in the harsh weather conditions of Mars. Lastly, I also though Ryan did well in reviewing the article. In the last paragraph, he explained that the article was interesting, from his perspective, and well written. His reasons for liking it were just, as many of them were why I enjoyed his review.
ReplyDeleteThe review was well written as a whole, but there were some things that could have been improved upon. For instance, although he did a good job in describing the experiments, but some of the terminology went over my head. This made it difficult to understand some elements of the article, which I would have been interested to learn about. Also, the review could have incorporated more reasons for liking or disliking the article, including how the article could have been improved from the viewpoint of the reader.
I learned that it is possible for microbes from Earth to survive on Mars. I also learned that there are restrictions on this statement, as they need to be covered by dust in order to survive the harsh weather conditions. After thinking for so long that no life from Earth would be able to survive in the harsh conditions of many planets, including Mars, this article and review were both eye-opening for me.
Ryan’s review about Alien Life on Earth and Earth Microbes on other planets was very well presented. Most articles about biology and the other sciences are very difficult to understand because of the complex terminology and other difficult language. However, Ryan’s review was very clear and made understanding the meaning of this article fairly easy. Ryan’s review was also very well written because he explained and elaborated on the main topics of the article. He clearly explained the purpose of the experiments and the outcomes of all of the scientists’ experiments. Lastly, I think Ryan’s review was well done because he chose an article that truly interested him. Sometimes its hard to read scientific articles, but Ryan’s choice was clearly very informative, complex, yet he found it interesting and wrote a very concise review.
ReplyDeleteThe review could have been made even better with a few corrections. First, Ryan talks about the experiments of the scientists. Even though he states the conditions that the experiments are done under, it would have been interesting if he made the content of the experiments clearer. Also, the review of this article would have been better if he related this experiment to past tests done to determine the ability to earth organisms to survive on mars and vice versa.
I was very impressed by the clarity of this review. Personally, I find it very difficult to understand science articles, but this review made this complex, but interesting experiment simpler to understand.
I think that this article is particularly well presented because though it has great depth, it is concise and does a good job disassembling some of the more complicated and intricate facets of such an intense scientific experiment. The methods in which the bacteria were tested are very detailed, and it is not in any way a mystery as to the credibility of the test. The article does a good job of examining the possible consequences of the findings of the tests, and refutes those using data. The article can also be applauded on its pertinence to our generation. Because of the destruction of earth through global warming and other destructive factors, it is interesting to know that researchers are looking into an Earth 2.0. The possibility of existing on Mars however is shaken when it says that bacteria are largely protected by the layer of dust.
ReplyDeleteThis article could have been better if there had been a little more detail on the exact purpose of proving the test and finding this research because it seems a little vague and may lead to misinterpretation. Additionally, I worry that though concise and well written, we may be missing some information, lost in brevity.
Overall this is a wonderful article because not only does it present interesting information but also because it does so in a clear manner which does not delve into the realms of intense biological terms. I was impressed to learn that an earth organism could survive under the protection of a mere 2c layer of dust. That seems like nothing, and especially dust does not seem like it would be able to protect anything to that extent.
Tony Tao
ReplyDelete12/23/2010
Ryan Review Overdue
The article presented the idea of contamination. This article brought to my attention the idea that other planets are natural environments too and we should not contaminate them. Just as we preserve natural environments on earth (for example by not importing non-native species) we should do the same with planets like mars. Another aspect that was well presented was the survivability of bacteria. Bacteria are extremely tough organisms. Even in foreign atmospheric gas compositions, freeze thaw cycles, low pressure and UV bombardment a bacterium can survive with a thin layer of dust. This point supports the idea that bacteria were living organisms among the earths prehistoric caustic conditions. It is even more surprising that by digging into the Martian crust bacteria may be able to survive indefinitely. Another thing that was great about the article was how specific it was. For example, the author didn’t use vague measurements or generalizations. Specific amounts for given. 80 days was used for the bacteria test, 2 cm of dust is needed for bacteria survival, and ultraviolet light specifically is harmful to bacteria. These specific points allows the reader to extrapolate more solid ideas from the review.
The article could be better if the author wrote more about the subject. I am curious to know more about the testing conditions of bacteria for mars like conditions. More information on the scientists who performed the experiment as well as where the experiments took place would add more the review. I would have also liked to learn about the techniques and machinery used to test the bacteria. I was especially impressed by the toughness of bacteria as the review mentioned. I remembered reading article about the Apollo space missions and how certain bacteria were found on the hull of the rocket after launch. This points out the survivability of bacteria. All of this points to bacteria once living in much more caustic environments. Only if the bacterium is extremely tough can it thrive in such situations. The article provided great insight into biological testing.