Laura Cipiti Fall 2010 Cosmology CURR

“The surest sign that intelligent life exists elsewhere in the universe is that it has never tried to contact us.” Bill Watterson - creator of Calvin and Hobbes

 The ancient Greeks were the first Western thinkers to consider formally the possibility of life in the universe outside of earth.  In the 16 th century, the Copernican model (earth was not the center of creation) opened the door to all sorts of extraterrestrial thoughts.

 1930 discovery of Pluto and further attention of the possibility that life is on Mars.  1959 Two young phycists at Cornell University authored a 2- page article entitled “Searching for Interstellar Communications”. The modern search then began.  1960 Scientists began a search to hear signals from intelligent life.  1975 Viking mission to look for life on Mars.  1985 SETI was founded.  1995 Astronomers have discovered the first exo-planet outside of our solar system.  2002 Scientists find that Europa may have an icy surface  2010 Scientists confirmed ice on Mars

 Violent events with very short time-scales, supernova explosions to bring chemical elements to life from stars, collisions between little planets crashing together to make bigger planets, and a quiet period to slowly evolve life.

 Our moon stabilizes the earth’s axis and helps control our climate.  The location of earth in our solar system prevents over exposure from our sun (Habitable zone).  Most stars in the universe are smaller than our sun, which would require planets to orbit closer to their sun to obtain necessary heat.  Jupiter protects us from being hit by many things such as comets and asteroids.  Having one sun provides a stable orbit.  Our distance from the sun gives us an atmosphere and liquid water, which can be maintained.  Liquid water seems to be an essential requirement for life.

 Scientists can’t seem to agree  Extremophiles- It has been proven that life does NOT need water to exist  Benton Clark (astrobiologist with University of Colorado) says, “Our criteria for life may be too specific.” We may only know what it is when we see it.  Life Beyond Earth video (10 mins) Life Beyond Earth video

 Europa (Jupiter)  Titian(Saturn)  Ganymede (Jupiter)  Enceladus (Saturn) Enceladus  Exo-solar planets  Mars

 NASA (2 mins.) NASA  Hubble, Kepler, multiple telescopes, plus future missions plus future missions  SETI (Search for Extraterrestrial Intelligence)  Frank Drake (3 mins.) Frank Drake  European Space Agency  French CoRoT mission and Gaia  Canadian Space Agency  MOST mission  Other Other

 NASA has created an Planetary Protection branch. Planetary branch.  Their mission is to prevent biological cross-contamination that could result from NASA’s solar system exploration missions.  So we won’t “discover” life we brought with us.

 October 5 - At Keck Observatory in Hawaii they discovered a new planet circling Gliese 581 star. It is within the habitable zone. This star has now 6 planets circling around it. This is the first discovery of a potential Earthlike world.  October 28 - NASA study suggests 1 out of every 4 stars may host Earth size planets.  Nov. 11 James Webb Space Telescope will be delayed at least another year.  Nov. 13 Chemists uncover a new chemical reaction that could allow scientists to gain information from ancient rocks to find out what the atmosphere of Mars was like hundreds of millions years ago. Recent News

 Alien Earths Alien Earths  Seti at home Seti at home  Nasa’s Planet QuestPlanet Quest

 Hamilton, C. (2001, November). Life beyond our solar system. Retrieved from  Finnes, E. (2008, August). Extremophiles [Web log message]. Retrieved from  Woodmansee, Laura. (2001). If life exists on mars, our robotic probe may have brought it there. Space Daily, Retrieved from  Mullen, L. (2002). Defining life. Astrobiology Magazine, Retrieved from  Balthaser, D. (2000, July). Pros and cons of life existing elsewhere. Extraterrestrial contact, 1472, Retrieved from  Globalimmersion, C. (Producer). (2009). Are we alone. [Web]. Retrieved from  Freethinker, F. (Producer). (2009). Life beyond earth. [Web]. Retrieved from  Zimmer, H. (Producer). (2009). Alien life on titan or europa. [Web]. Retrieved from  Ransford, M. (2008, June). The search for extraterrestrial life: a brief history. Popular Science, Retrieved from  Little, D. (1999, January). The search for life in the universe. Retrieved from  Degrasse, N. (2002, June). The search for life in the universe. Retrieved from

Sources continued…  Little, D. (1999, January). The search for life in the universe. Retrieved from  Degrasse, N. (2002, June). The search for life in the universe. Retrieved from  Lawler, A. (2009). Is jupiter's bizarre moon our best hope of finding extraterrestrial life?. Discover Magazine, Retrieved from bestextraterrestrial-life/article_view?searchterm=europa%20%20%20life&b_start:int=1http://discovermagazine.com/2009/sep/28-is-this-bizarre-moon-our- bestextraterrestrial-life/article_view?searchterm=europa%20%20%20life&b_start:int=1  Honig, M. (2010, February). The oceans of enceladus. Retrieved from  Woollacott, E. (2010, February). Ingredients for life present on saturn's moon. Retrieved from saturns-moon=18902