Transcript PH1600: Introductory Astronomy

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PH1600: Introductory Astronomy
Lecture 24: Life: Are We Alone?
PH1600: Introductory Astronomy
Lecture 22: Life: Are We Alone?
Study: Chapter 20 in The Cosmos book
Next Lecture: Chapter 20: UFOs and Pseudoscience
School: Michigan Technological University
Professor: Robert Nemiroff
Book: The Cosmos by Pasachoff & Filippenko
Online Course WebCT pages:
http://courses.mtu.edu/
This class can be taken online ONLY, class
attendance is not required!
You are responsible for…
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Reading the book
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APODs posted during the semester
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One chapter per “quiz period”
Anything from that chapter can appear on
quizzes or tests, even if I never mention them
during my lecture(s)
This quiz period covers Chapters 18
APOD review every week during lecture
Completing the Quizzes
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Chapter 1, 2, 4, 6, 7, 8, 10, 11, 13, 14, 15, 18
& 19 quizzes already due
Chapter 20 Quiz incorporated into Final Exam
See WebCT at http://courses.mtu.edu/ for
details
The Drake Equation:
N = R* x fp x ne x fl x fi x fc x L
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N is the number of civilizations in our Galaxies
that are contactable
R* is the rate of star formation
fp is the fraction of stars that have planets
ne is the number of habitable planets per above
star
fl is the fraction of above planets that develop life
fi is the fraction of above life planets that develop
intelligent life
fc is the fraction of intelligent life planets that are
contactable
L is the expected lifespan of such a intelligent life
civilization
The Drake Equation
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Possible plausible values:
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R*=10 stars/year; fp=0.5; ne=2
fl=1; fi=0.01; fc=0.01;
L=10,000 years
Then N~10
Where are they: Fermi Paradox
Life in Our Solar System
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Mars
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Jupiter’s MoonEuropa
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Hydrocarbon seas, rain
Saturn’s Moon Enceladus
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Underground seas
Frozen fish in orbit?
Saturn’s Moon Titan
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Ancient or modern
Underground seas
Anywhere else?
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Cloudtops of Jupiter?
Water Ice in a Martian Crater
Credit: G. Neukum (FU Berlin) et al., Mars Express, DLR, ESA;
Image created for and Copyright: Nature
APOD: 2005 July 20
Unusual Plates on Mars
Credit: G. Neukum (FU Berlin) et al., Mars Express, DLR, ESA
APOD: 2005 February 28
Light Deposits Indicate Water Flowing on Mars
Credit: Mars Global Surveyor
APOD: 2006 December 12
Pictured: An Ancient Martian?
Credit: D. McKay (NASA /JSC), et al., NASA
APOD: 1997 August 16
Early Microscopic Life on Mars?
Credit: courtesy NASA
APOD: 1996 August 7
Tantalizing Titan
Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA
APOD: 2004 October 28
Methane Rain Possible on Titan
Illustration Credit & Copyright: Mark Garlick (Space-art.co.uk)
APOD: 2006 August 2
Possible Methane Lakes on Titan
Credit: Cassini Radar Mapper, JPL, ESA, NASA
APOD: 2006 July 31
Enceladus and the Search for Water
Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA
APOD: 2006 March 10
Fountains Discovered on Saturn's Enceladus
Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA
APOD: 2005 December 5
Enceladus Ice Volcanos
Illustration Credit & Copyright: Michael Carroll
APOD: 2006 June 8
The Very Large Array of Radio Telescopes
Credit: Dave Finley, AUI, NRAO, NSF
APOD: 2006 May 14
A Big Dish at the VLA Radio Observatory
Credit & Copyright: Victor Bobbett
APOD: 2006 November 29
Arecibo: The Largest Telescope
Credit: NAIC, Cornell U., NSF
APOD: 1998 November 29
Radio, The Big Ear, And The Wow! Signal
Credit and Copyright: Rick Scott
APOD: 1998 September 17
How to Search for Aliens
Credit: SETI@home, UC Berkeley SETI Team
APOD: 1999 May 17
An Anomalous SETI Signal
Credit & Copyright: SETI League
2004 March 7
The Voyagers' Message in a Bottle
Credit: Voyager Project, JPL, NASA
APOD: 2002 August 31
A Message From Earth
Credit: Frank Drake (UCSC) et al., Arecibo Observatory (Cornell, NAIC)
2005 March 13
A Cosmic Call to Nearby Stars
Credit & Copyright: Yuvan Dutil & Stephane Dumas
2006 April 2
M13: The Great Globular Cluster in Hercules
Credit & Copyright: Eddie Guscott
APOD: 2004 May 11
The Lost World of Lake Vida
Credit & Copyright: Thomas Nylen et al., NASA, NSF
APOD: 2004 April 4
Searching for Meteorites in Antarctica
Credit & Copyright: Ralph P. Harvey (CWRU),
Antarctic Search for Meteorites Program, NASA, NSF
APOD: 2002 December 26
A Meteorite From Mars
Credit: JSC, NASA
APOD: 1996 August 17
55 Cancri: Familiar Planet Discovered
Illustration Credit & Copyright: Lynette Cook
APOD: 2002 June 14
Other Worlds and HD 38529
Illustration Credit: Copyright 2000 Lynette Cook
APOD: 2000 August 10
Pictured: An Ancient Martian?
Credit: D. McKay (NASA /JSC), et al., NASA
APOD: 1997 August 16