Hannah Pepper-Cunningham (03/10/04)
I really enjoyed yesterday's class and of course absolutely loved our crazy bliny night. I have learned next to nothing about either geology or planetology, and so a lot of my enjoyment of the readings and the class was the type of enjoyment one gets when delving into something that is both completely new and completely interesting.
I hadn't previously realized how greatly Mars and the Earth differed in their respective dynamisms of geological processes. Nor had I realized what an impact the movement of tectonic plates had had on the longevity of the Earth's geological features. My sense of perspective changed really rapidly when I realized that such processes had destroyed all but – 2 billion was it? – years of a much longer geological history. Thinking about it in such a perspective made me feel as if I were riding on a rapidly moving plate that would be subsumed into the earth in what is, in the grand scheme of things, a minute period of time.
We learned in class that while the Earth and Mercury have only preserved 2 billion (I think) years of a 4.5 billion year geological history, Mars has preserved the entire thing. This makes sense given that we also learned that where Earth has tectonic plates, Mars has none. However, in class we also discussed the possibility of tectonic plates having existed on Mars in the past. Could it be possible that if there had been such tectonic activity in the past, it could have similarly destroyed some of Mars' geological history? In addition, I had two questions relating to this discussion that may or may not have already been answered in class. 1. How do scientists know that the planets were created 4.5 billion years ago? and 2. How do geologists know that Mars' geological features date back 4.5 billion years?
Even before this class, I could name a good amount of differences between Earth and Mars that would affect the latter's ability to support life. However, yesterday, I learned about an aspect of both planets that had not even entered my mind previously: the obliquity of the planet's rotation. Although I already knew that the moon is a stabilizing factor in the earth's obliquity, I still think it is really cool. The Soffen article suggested that the “wildly varying obliquity” of Mars “would make it more difficult to maintain the stable climate needed to sustain life.” Soffen states that “the obliquity of Mars has undergone wide swings in the past. My question in response to this statement is, how long ago is this past? Could it be possible that at some point in the past, Mars could have had a moon that would have stabilized Mars' axis? Is it possible for scientists to determine this?
Bliny night, as I have already said was fantastic! I was so excited to get to help make the bliny! Well, I think that maybe “help make the bliny” would be exaggerating a bit, but it was still fun. I got to talk to Misha (bliny-maker Misha), which was some crazy times. He is studying Venus and told me that the set of forces that have shaped Venus' geological history are completely different than those such as earthquakes and plate tectonics that have shaped Earth's geological history. The diversity of forces that can shape a planet's geological history really illustrated for me how potentially different Earth and Mars can be, despite having many similarities. In addition, I also enjoyed listening to Misha, prompted by Jay, describe Venus' pancake volcanoes using bliny.I had another interesting discussion with Sergei Khrushchev, but it didn't really have to do with Space Exploration. I wanted to ask him about his feelings regarding both the legacy of Soviet communism and democracy in Russia. He said that one flaw in the way in which the West looks at communism is that it is unable to separate the theory of communism from a country's practice of communism. According to him, Soviet communism departed from theoretical communism in the early 1920's. He said basically that Soviet communism was almost as much influenced by the Soviet political mindset as it was by communist theory and that Russian communism “became the Russian empire,” Chinese communism the Chinese empire, and that neither of these two resembled communism in North Korea, Cuba, or Hungary. As for the prospects of Russian democracy, Khrushchev said that Russia has not really had a democratic mindset throughout its history. One aspect of democracy that, according to Khrushchev, has not been a part of the Russian political culture is a freedom of information flow. However, he felt that in this age of the Internet and telecommunications, most countries will be forced to allow for more freedom of information. This, he expressed, has the potential to be a major democratizing force. This conversation was very enlightening to me, as was the entire day.