Transcript The Search for Spock The Scientific Search for

The Search for Spock
The Scientific Search for Extraterrestrial Life
Or Graur
Student Seminar 26.03.09
The Drake Equation
N=R*fp*ne*fl*fi*fc*L
The Water Hole
1959: Morrison & Cocconi
H - 21 cm -> 1.42 GHz
OH - 18.3 cm -> 1.64 GHz
Hipschman R., Project SERENDIP: Searching for Life in the Cosmos, What’s New in the World, 29.10.97
Project OZMA: 1960
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Two G stars: Epsilon Eridani & Tau Ceti
1420 Mhz
85 ft radio telescope at Green Bank
150 hours
nada
The Goldilocks Region
Kasting, Whitmire & Reynolds (1993)
The GHZ
Lineweaver, et al. (2004)
The GHZ
Lineweaver, et al. (2004)
Phoenix: 1995-2004
Parkes 64m + Mopra 22m (Australia)
 Green Bank 140ft + Woodbury (USA)
 Arecibo (Puerto Rico)
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800 G-type stars out to 200 lyr.
 1-3 Mhz region, 1Hz resolution
 Conclusion: “We live in a quiet
neighborhood.”
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SERENDIP: 1979 -
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Phase
#channels
I
100
II
65K
III
4M
IV
168M
piggybacking
Signal resolution of 0.6 Hz
Sullivan, et al. (1997)
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0.25 MB = 50 seconds of a 20 kHz chunk
Signal widths of 0.1-2000 Hz
Sullivan, et al. (1997)
Berkeley Open Infrastructure
for Network Computing
~25 projects:
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SETI@home
LHC@home – LHC simulations
Einstein@home – pulsar survey based on LIGO,
GEO
Chess960@home
SIMAP – similarity between proteins
Rosetta@home – 3-D shape of proteins
Berkeley Open Infrastructure
for Network Computing
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680,000 participants in 245 countries
1,000,000 computers
400 TeraFLOPS (more than IBM’s 2006
supercomputer BlueGene)
12 Petabytes of free disk space
SETI@home: 2.7 million years of
computer time
Anderson D. P., A Million Years of Computing, talk at the
Singapore National Library, May 2006
Allan Telescope Array: 2007 -
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Hat Creek Radio Observatory (N Cal)
Dedicated wholly to SETI
350 6.1m antennae => S<100m2
0.5-11 GHz
Two paths:
• non-natural signals from 105-106 stars out to
1000 lyr.
• Directed message in the water hole region
from 1010 stars in inner galactic plane
ATA – other objectives
Classify 2.5x105 extragalactic radio
sources as either AGN or starburst
galaxies.
 Gravitational lens candidates for dark
matter/energy detection.
 Metallicity in the Milky Way
 Radio transients
 And much, much more
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Lick Optical SETI: 2000 -
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5,039 F,G,K,M stars out to 200 lyr.
300-900 nm range
Search for nanosecond laser pulses
Other surveys: Leuschner, Harvard Smithsonian,
Princeton, Columbus-Ohio
Central Casting Syndrome
Central Casting Syndrome
Life on Mars? Canals
1877: Giovanni Schiaparelli (1877)
Life on Mars? ALH84001
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Discovered: 27.12.84
Shocked: 06.08.96
“structures” 20-100 nm in diameter
Traces of amino acids and PAHs (polycyclic
aromatic hydrocarbons)
Martian? Antarctic? Not biological?
Conclusive? Eh…
Life on Mars? Methane!
Mumma, et al. (2009)