Astronomy: Our Solar System
Blogs concerning current and interesting developments surrounding our solar system
- Blog 8: My Newly Formed Perspective
From NASA It’s weird to think about how this will be the final assignment for our astronomy class. Throughout the semester, my understanding of the vast universe we exist in has deepened, further changing my perspective of our world and humanity’s role within it. In this class, we studied the basic processes of the universe, from its formation to the geographic and atmospheric processes of planetary bodies. I think one of the hardest concepts to understand or rather accept was the vastness of our universe. It is always said that the universe is massive, infinite, and further expanding, however, I don’t think I fully understood how true those concepts were before this class. It’s hard to understand the scale of the universe from our positions on earth. We considered location changes over states or countries as large measures of distance, so it is truly jarring when faced with the infinitely larger scale that the universe plays out on. This is true with both distance and time. The distance of planets, stars, and galaxies to Earth all exposed the vastness of the universe, however, the increment of time that humanity has existed within it is also incredibly small. In class, we looked at the Cosmic Calendar which maps the formation and development of the universe, and within this calendar, humanity is only present for a few seconds of the last day.
My perspective on life outside of Earth also changed. I always somewhat believed that somewhere within the universe there would be other life forms, however, now I truly understand that this is almost a certainty. When you think about the crazy number of stars within our universe and how common planetary bodies are that orbit these stars it is almost impossible not to believe in extraterrestrial life. Not to mention that even within our solar system there is still a possibility for life to exist on a few different worlds, like Europa, Io, or Titan. - Blog 7: Extremophiles
Extremophiles are organisms that thrive within severe abiotic environments while maintaining the ability to grow and reproduce. These organisms inhabit areas of extreme temperature, pressure, salinity, acidity, and radiation, surviving through environmentally defined adaptations. Extremophilic organisms are based within both prokaryotic and eukaryotic life, meaning their existence ranges throughout all domains of life. Through the research of such organisms, insights are observed from each environmentally refined adaptation, leading to a deeper understanding of biological function and the range of environmental conditions under which life can survive. Extremophiles are further subdivided into categories based on the environment they exist in. These include thermophiles and psychrophile (characterising extreme warm and cold temperatures), barophiles (high pressure levels), halophiles (extreme salinity), and acidophiles (or conditions with high acidic ph values).
Helicobacter pylori is an example of an extremophile, specifically an acidophile, meaning it thrives in extremely acidic environments. H. pylori is a bacteria that inhabits the high acidic conditions of the stomach. This microbiota secretes the enzyme urease that protects to organisms from the stomach’s hydrochloric acid.
- Blog 6: Huygens’s Descent to Titan
The Cassini orbiter, initially launched on October 15, 1997, traveled seven years with the objective to relay observations of Saturn and its satellites. Attached to this spacecraft was also the Huygens probe, designed to enter the atmosphere and land on the surface of Titan, Saturn’s largest moon. On January 14, 2005, Huygens executed its mission; descending into Titan’s atmosphere and landing on its surface through a series of parachutes. Before the descent little was known about the surface of Titan because of atmospheric haze that shrouded the entire moon. However, images sent back to the Cassini spacecraft during Huygens’s fall and landing revealed much about Titan’s atmosphere and surface. Through the probe’s descent, much of the atmospheric composition and weather patterns could be inferred. It was observed that Titan had a much heavier atmosphere than expected due to concentrated levels of dust particles. Wind and weathering pattern could also be inferred as Huygens parachuted to the surface and was carried by winds. From this, it was concluded that winds circulated worldwide from north to south. However, the more surprising imagery came when the probe reached Titan’s surface as it revealed, through a slight haze, geography similar to earth. Present on the surface was evidence of liquid erosion, believed to have been produced through running liquid methane, that had carved out channels along Titan’s surface. Resulting in larger evidence of lakes and oceans. Also, in the final landing spot of Huygens, there were clear depictions of rounded and errored rocks that express characteristics of a previous river bed.
Video From NASA
Astronomy: The Solar System 