Aliens Fp Self Prediction

Aliens Fp Self Prediction - which exist in our own solar...

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Sijia Hao Astro 106 – Aliens 24 March 2011 The variable f p represents the fraction of stars in our Milky Way galaxy that have planets that orbit them. The actual number depends on an estimate of the amount of stars in the galaxy in the first place, then how many of those stars feasibly support planetary systems. Estimations of the fraction are based on data collected by the Hubble Space Telescope and other telescopes, which detect a number of stars and whether or not they have planets in orbit. There are two general ways of detection – indirect, which uses gravitational and transitional forces to infer a planet’s presence, and direct, which relies on solid visual verification of the existence of the planet. The Doppler Shift’s properties can be used to gauge whether a planet is moving toward or away from the Earth. There are two main types of planets that exist, gas giants and terrestrial planets, both of
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Unformatted text preview: which exist in our own solar system. The Telescope frequently spots protoplanetary disks around stars, which are debris of gas and dust where planets may be formed, suggesting that planetary formations around stars is not at all uncommon. There may be even more planets than the telescopes show because the telescopes can only detect planets that are the same size or bigger than that of the Earth; it is likely that many smaller planets have yet to be discovered. Even today, new planets are being discovered every day. Using the data that telescopes have gathered over the years, namely an educated estimation of the amount of stars there are in the galaxy and then how many of those stars have planets, a fraction can be derived. Currently, f p = about 0.4. http://library.thinkquest.org/C003763/index.php?page=origin09 Lecture slides Feb 28...
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This note was uploaded on 01/25/2012 for the course ASTRO 106 taught by Professor Bell during the Winter '10 term at University of Michigan.

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