Frank Summers Presentation On Comets At The Space Telescope Science Institute

Submitted By barnone312
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On November 11th, I attended speaker Frank Summers’ presentation on comets at the Space Telescope Science Institute. During the presentation, Mr. Summers talked about some of the greatest comets in history along with several of their characteristics. Since the year 373 BCE, astronomers have observed 71 different comets, the most of which were observed in the 1900’s (9). Interestingly enough, there have been 22 different appearances of the Comet Halley over the years. Some of the more recognizable characteristics of comets that have been observed over the years are their visibility during the daytime and their tails that can be up to 100 degrees long. Most comets broke into several pieces during their flight through the space, often colliding with other asteroids or deteriorating as they break through the earth’s atmospheres. The next thing Mr. Summers discussed was what lies at the heart of a comet. According to scientists, the nucleus of a comet is very crater-like. It consists of five nuclei and is irregular shaped. It is very small and consists of dust particles, C02, ammonia, and methane (which gives the comet its bluish-green look). Most asteroids are located in the Kuiper Belt, which like the asteroid belt, consists of remnants from the Solar System’s formation. Unlike the space objects found in the asteroid belt, those found in the Kuiper Belt are composed largely of frozen volatiles such as methane, ammonia and water. In mid to late November, the Comet ISON may be visible here on earth before dawn on November 17th. On