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The SETI@home, SERENDIP, SEVENDIP, Astropulse, and SPOCK SETI Programs. ‘ Dan Werthimer, Dave Anderson, Jeff Cobb, Paul Demorest, Eric Korpela, Cecile Kim, Geoff Marcy University of California, Berkeley. http://seti.berkeley.edu/. NOT FUNDED. NOT FUNDED. NOT FUNDED. Porno in space:
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The SETI@home, SERENDIP, SEVENDIP, Astropulse, and SPOCK SETI Programs ‘Dan Werthimer, Dave Anderson, Jeff Cobb, Paul Demorest, Eric Korpela, Cecile Kim, Geoff Marcy University of California, Berkeley http://seti.berkeley.edu/
Porno in space: FUNDED!
Drake Equation • N=R fs fp ne fl fi fc L • N = number of communicating civilizations in our galaxy
First Radio SETI • Nikola Tesla (1899) • Announces “coherent signals from Mars” • Guglielmo Marconi (1920) • Strange signals from ET • Frank Drake (1960) • Project Ozma • one channel, 1420-1420.4 MHz
Signal Types 1. Artifact (radio, radar, ~TV, ????) 2. Deliberate (easy to decode, pictures, language lessons) First civilization we contact is likely to be a billion years ahead of us.
Targeted Search Strategy: Project Phoenix - Seti Institute Sky Survey Strategy: Serendip, SETI@home - UC Berkeley Beta - Harvard Southern Serendip - Australia Meta II - Argentina Seti Italia - Medicina Obser.
Quick History of Berkeley SETI • Radio SETI • SERENDIPSearch for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations • SERENDIP I-III (1979-1997) • SERENDIP IV (1997-) • SERENDIP V (2004-)
The Berkeley Radio SETI Family Tree SERENDIP SERENDIP II OSU SERENDIP III SETI Italia SETI@home Data Recorder SETI@home Clients SERENDIP IV Southern SERENDIP SETHI@Berkeley HI Survey AstroPulse Pulse Survey SETI@home II Data Recorder SETI@home II Clients SERENDIP V
SERENDIP IV Photos Courtesy NAIC Arecibo Observatory, a facility of the NSF • 168M channels • 100 MHz Band centered on 1420 MHz • Carriage House 1 line feed • Operating since 1997
Why SETI@home? • Coherent Doppler drift correction • Narrower Channel Width->Higher Sensitivity • Variable bandwidth/time resolution • Search for multiple signal types • Gaussian beam fitting • Search for repeating pulses Problem: Requires TFLOP/s processing power. Solution: Distributed Computing
SETI@home Statistics TOTAL RATE
Master Science Database Candidate Identification Result Verification Online Science Database The Internet Work Unit Storage Data Server 3.8 Million Volunteers Data splitters Tapes from Arecibo Volunteer Statistics Database Web Server Structure of SETI@home
The Input and Output • 1 Work-Unit=9.8 kHz x 220 samples (107 sec.) • 256 Workunits across 2.5 MHz band centered on 1420.0 MHz. • Workunits overlap in time by ~25 sec. • Each workunit sent to multiple computers for result verification • Typically 4 TFLOP/workunit. • Output=Typically ~5 potential signals.