SETI on the SKASETI on the SKA

Dan Werthimer Dan Werthimer University of California, BerkeleyUniversity of California, Berkeley

http://seti.berkeley.edu/

•SETI historySETI history

•SETI todaySETI today

•SETI future (SKA)SETI future (SKA)

•Signal processingSignal processing

NOT FUNDED

NOT FUNDED

NOT FUNDED

Porno in space:

FUNDED!

First Radio SETIFirst Radio SETI• Nikola Tesla (1899)Nikola Tesla (1899)

– Announces “coherent signals from Mars”Announces “coherent signals from Mars”

• Guglielmo Marconi (1920)Guglielmo Marconi (1920)– Strange signals from ETStrange signals from ET

• Frank Drake (1960)Frank Drake (1960)– Project Ozma Project Ozma

– one channel, 1420-1420.4 MHzone channel, 1420-1420.4 MHz

Traditional SETI dogma: Traditional SETI dogma:

ultra narrow band sine wavesultra narrow band sine waves

barycentric, beacons, FGK starsbarycentric, beacons, FGK stars

21 cm21 cm

Future dogma: Future dogma:

many bandwidths, frequencies,many bandwidths, frequencies,

drifting signals, pulses,drifting signals, pulses,

M stars, galaxiesM stars, galaxies

It’s naïve to think we know how It’s naïve to think we know how best to search today, given our best to search today, given our history of changing SETI history of changing SETI fashion. fashion.

• Multiple strategy is bestMultiple strategy is best

(IR, Vis, Radio, pulse, continuous, targetted(IR, Vis, Radio, pulse, continuous, targetted

sky survey…)sky survey…)

• Half of astronomy discoveries are Half of astronomy discoveries are serendipitous serendipitous

• Examine glitches in data Examine glitches in data

• Data Mining ExperimentsData Mining Experiments

OPTICAL SETIOPTICAL SETI

1961 Charlie Townes Paper 1961 Charlie Townes Paper

largely ingored until 1999largely ingored until 1999

1971 Cyclops report calculates radio >> 1971 Cyclops report calculates radio >> opticaloptical

Today’s lasers can communicate across Today’s lasers can communicate across galaxygalaxy

Optical SETI experimentsOptical SETI experiments

• Lick Observatory Lick Observatory

(Lick, Seti Institute, Berkeley)(Lick, Seti Institute, Berkeley)

• Harvard (targetted Harvard (targetted sky survey) sky survey)

• Princeton Princeton

• BerkeleyBerkeley

10-meter Keck Telescope10-meter Keck Telescope

Survey: 650 F8 – M5 V, IVSurvey: 650 F8 – M5 V, IV

Hipparcos V < 8.5B-V > 0.55 (F8V)Sep > 2 arcsecAge > 2 Gyr

Keck Optical SETI – Data Keck Optical SETI – Data MiningMining

• Geoff Marcy, Amy Geoff Marcy, Amy ReinesReines

• 650 stars (planet 650 stars (planet data)data)

• Echelle Echelle SpectrometerSpectrometer

• Can detect 10KW Can detect 10KW narrow band signalnarrow band signal

(10 KW laser on 10 (10 KW laser on 10 meter telescope)meter telescope)

SETI GOAL:

SkyCoverage * FreqCoverage * Sensitivity^-3/2 * Nsignaltypes

solid angle vs number of nearby FGK stars?

FreqCoverage vs Noctaves?

Pulses vs sinewaves vs drifting vs broadband…?

FreqCoverage, SkyCoverage, signal types: other telescopes

sensitivity: SKA

Radio SETIRadio SETITargetted Search StrategyTargetted Search Strategy

Project Phoenix - Seti InstituteProject Phoenix - Seti Institute

Sky Survey StrategySky Survey Strategy

Serendip, SETI@home - UC BerkeleySerendip, SETI@home - UC Berkeley

Southern Serendip - AustraliaSouthern Serendip - Australia

Meta II - ArgentinaMeta II - Argentina

Seti Italia - BolognaSeti Italia - Bologna

SETI Programs at the SETI Programs at the University of University of CaliforniaCalifornia

NAME TIME SCALE SEARCH TYPE

SERENDIP 1 second Radio sky survey

SETI@home ms to second Radio sky survey

ASTROPULSE us to ms Radio sky survey

SEVENDIP ns Visible targetted

SPOCK 1000 seconds Visible targetted

Dyson Search Years IR excess

University of California, Berkeley SETI University of California, Berkeley SETI ProgramProgram• Graduate Students Graduate Students

Chen Chang, Karl Chen, Paul Demorest, Nia Imara, P. Monat, A. Chen Chang, Karl Chen, Paul Demorest, Nia Imara, P. Monat, A. ParsonsParsons

• Undergraduate StudentsUndergraduate Students

Noaa Avital, Brian Boshes, Henry Chen, Charlie Conroy, Chris Noaa Avital, Brian Boshes, Henry Chen, Charlie Conroy, Chris Day, Daniel Hsu, Wonsop Sim, Ryo TakahashiDay, Daniel Hsu, Wonsop Sim, Ryo Takahashi

• Astronomers and Computer ScientistsAstronomers and Computer Scientists

David Anderson, Bob Bankay, Jeff Cobb, Court Cannick, Eric David Anderson, Bob Bankay, Jeff Cobb, Court Cannick, Eric Korpela, Matt Lebofsky, Jeff Mock, Dan Werthimer, Rom WaltonKorpela, Matt Lebofsky, Jeff Mock, Dan Werthimer, Rom Walton

• Administrative Staff - NoneAdministrative Staff - None

SERENDIP IVSERENDIP IV

• 168M channels168M channels

• 100 MHz Band centered on 1420 100 MHz Band centered on 1420 MHzMHz

• Carriage House 1 line feedCarriage House 1 line feed

• Operating since 1997Operating since 1997

Photos Courtesy NAIC Arecibo Observatory, a facility of the NSFPhotos Courtesy NAIC Arecibo Observatory, a facility of the NSF

Why SETI@home?Why SETI@home?

• Coherent Doppler drift correctionCoherent Doppler drift correction– Narrower Channel Width->Higher SensitivityNarrower Channel Width->Higher Sensitivity

• Variable bandwidth/time resolutionVariable bandwidth/time resolution

• Search for multiple signal typesSearch for multiple signal types– Gaussian beam fittingGaussian beam fitting

– Search for repeating pulsesSearch for repeating pulses

Problem: Requires TFLOP/s processing power.

Solution: Distributed Computing

The SETI@home ClientThe SETI@home Client

5,064,550 participants (in 226 countries)

2,000 per day

2 million years computer time

1,200 years per day

4*1021 floating point operations

65 Tera-flops

SETI@home Statistics

TOTAL RATE

SETI@home in CanadaSETI@home in Canada• 255,426 participants (0.8% of 255,426 participants (0.8% of

population)population)

• 112,000 years of computer time112,000 years of computer time

• 72 million work units72 million work units

Web site: 2 million hits/dayWeb site: 2 million hits/day 200,000 visitors/day 200,000 visitors/day

(stats & games popular; science less (stats & games popular; science less

popular)popular)

100,000 children, families100,000 children, families (including congress members and their kids)(including congress members and their kids)

> 7,000 schools> 7,000 schools

Desired SKA ParametersDesired SKA Parameters

• Wide bandwidthWide bandwidth

• 1 M beams1 M beams

• fat beamsfat beams

• short dwell times (~ 100 seconds)short dwell times (~ 100 seconds)

Gaussian CandidatesGaussian Candidates

BOINCBOINC

• Berkeley Open Berkeley Open Infrastructure for Network Infrastructure for Network ComputingComputing

– General-purpose distributed General-purpose distributed computing framework.computing framework.

– Open source.Open source.

– Will make distributed Will make distributed computing accessible to computing accessible to those who need it. (Starting those who need it. (Starting from scratch is hard!)from scratch is hard!)

BOINC ProjectsBOINC Projects• SETI@home (Berkeley))SETI@home (Berkeley))

• Astropulse (Berkeley)Astropulse (Berkeley)

• ClimateModeling@home (Oxford)ClimateModeling@home (Oxford)

• Einstein@homeEinstein@home (Caltech) (Caltech)

• Folding@homeFolding@home (Stanford) (Stanford)

• ParticlePhysics@homeParticlePhysics@home (CERN) (CERN)

• Stardust@homeStardust@home (U. Wa, Berkeley) (U. Wa, Berkeley)

AstroPulseAstroPulse• Sky surveySky survey

– Covers decs 0 to 30Covers decs 0 to 30

– ~3 years of data recorded so far.~3 years of data recorded so far.

• Good time resolutionGood time resolution– Sensitive to 0.4 µs radio pulses at 21 cmSensitive to 0.4 µs radio pulses at 21 cm

• DM rangeDM range– -1000 to +1000 pc/cm-1000 to +1000 pc/cm33

• SensitivitySensitivity– 1010-18-18 W/m W/m22 peak (Coherent de-dispersion) peak (Coherent de-dispersion)

Piggyback ALFA Sky SurveyPiggyback ALFA Sky Survey• Improved sensitivity Improved sensitivity

– Tsys, integration timeTsys, integration time

• Uniform sky sampling Uniform sky sampling – galactic plane concentrationgalactic plane concentration

• Multibeam RFI rejectionMultibeam RFI rejection

• Larger BandwidthLarger Bandwidth

Search for Optical/Radio Signals from Dyson Sphere Candidates|

Charlie Conroy

• Looked for IR excess from >500 stars

• All stars had age > 1 Gigayear

• 33 stars found with 12m excess

• Searched for anomalous radio detection using SETI@home and SERENDIP IV databases

• Searched for optical pulse emission using OSETI experiment

• Thus far, none of the 33 sources have shown anomalous optical or radio emission

Color excess using 2MASS K band data and 12, 25, 60, & 100 micron IRAS data. An excess at K-[12] is clearly visible and disappears by K-[25]. Dotted lines are Gaussian fits to the distributions. The 33 IR excess candidates have K-[12] > 3 above the mean.

‘‘Prelude’ Precedes SonATAPrelude’ Precedes SonATAIn Fall 2004In Fall 2004For Use On The ATA-32 For Use On The ATA-32

3 beams with 30 MHz each – PCs with accelerator cards

Future SETI Future SETI SpectrometersSpectrometers2015 4 THz 400 beams

10 GHz each2020 128 THz 12,800 beams

2025 4000 THz 40,000 beams

2030 128,000 THz 1M beams

Moore’s Law in FPGA Moore’s Law in FPGA worldworldComputational Density Comparison

1000

10000

100000

1000000

10000000

10/28/1995

3/11/1997

7/24/1998

12/6/1999

4/19/2001

9/1/2002 1/14/2004

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6/19/1997

1/5/1998

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3/15/2000

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11/5/2001

5/24/2002

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100X More efficient100X More efficientthan micro-processors!than micro-processors!

3X improvement3X improvementper year!per year!

Multi-Purpose FPGA-Multi-Purpose FPGA-Based Spectrometer Based Spectrometer (NSF, A. Parsons)(NSF, A. Parsons)

XilinxVirtex-II 6000

FPGA

XilinxVirtex-II

1000FPGA

256 MB DRAM

AreciboFeed

Array

200 MhzADC

Compact PCIBackplane

Software

200 MhzADC

200 MhzADC

200 MhzADC

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SETI ApplicationsSETI Applications• ALFA Sky Survey (300 MHz x 7 beams)ALFA Sky Survey (300 MHz x 7 beams)

• Parkes Southern SERENDIPParkes Southern SERENDIP

• JPL/UCB/SI Survey (20 GHz Bandwidth)JPL/UCB/SI Survey (20 GHz Bandwidth)

• SETI Italia (Bologna)SETI Italia (Bologna)

• SETI@homeSETI@home

Astronomy ApplicationsAstronomy Applications• GALFA Spectrometer – Arecibo Multibeam Hydrogen SurveyGALFA Spectrometer – Arecibo Multibeam Hydrogen Survey

• Astronomy Signal Processor – ASP – Don Backer (pulsars)Astronomy Signal Processor – ASP – Don Backer (pulsars)

• ATA4 Correlator F Engine ATA4 Correlator F Engine

• Reionization Experiments (Backer (UCB), Chippendale/Ekers Reionization Experiments (Backer (UCB), Chippendale/Ekers (ATNF)) (ATNF))

Filter Response:PFB vs. FFT

Next Generation BoardNext Generation BoardBEE2 (2004/5) – Chen BEE2 (2004/5) – Chen ChangChang• 5 Xilinx XC2VP70 5 Xilinx XC2VP70

• 40 GB RAM (8 GB each chip, 13Gbit/sec/chip)40 GB RAM (8 GB each chip, 13Gbit/sec/chip)

• 18 10Gbit/sec infiniband ports18 10Gbit/sec infiniband ports

• 50 boards per rack, Tbit/sec infiniband switch50 boards per rack, Tbit/sec infiniband switch

• Applications:Applications:– 1 GHz, 1 Gchannel spectrometer (single board)1 GHz, 1 Gchannel spectrometer (single board)– Next Generation ATA backends (ata32 = 2 boards)Next Generation ATA backends (ata32 = 2 boards)– SKA imagingSKA imaging

B2 Module: board layoutB2 Module: board layout• 5 compute 5 compute

elements on a elements on a boardboard

• Up to 400 billion Up to 400 billion CMAC/s CMAC/s performanceperformance

• communication communication bandwidth: bandwidth:

– 240 Gbps on-240 Gbps on-board 360 board 360 Gbps off-boardGbps off-board

Global InterconnectsGlobal Interconnects• Commercial Infiniband Commercial Infiniband

switch from Mellanox, switch from Mellanox, Voltaire, etc.Voltaire, etc.– Packet switched, non-Packet switched, non-

blockingblocking

– 24 ~ 144 ports (4X) per 24 ~ 144 ports (4X) per chassischassis

– Up to 10,000 ports in a Up to 10,000 ports in a systemsystem

– 200~1000 ns switch latency200~1000 ns switch latency

– 400~1200 ns FPGA to FPGA 400~1200 ns FPGA to FPGA latencylatency

– 480Gbps ~ 2.88Tbps full 480Gbps ~ 2.88Tbps full duplex constant cross duplex constant cross section bandwidthsection bandwidth

– <$400 per port<$400 per port

ComputeNode

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ComputeNode

#1

Infiniband Crossbar Switch

Ethernet Switch

19” 48RU Rack Cabin 19” 48RU Rack Cabin CapacityCapacity

• 40 compute nodes in 5 chassis (8U) per 40 compute nodes in 5 chassis (8U) per rackrack

• Up to 16 trillion CMac/s performance per Up to 16 trillion CMac/s performance per rackrack

• 250 Watt AC/DC power supply to each 250 Watt AC/DC power supply to each bladeblade

• 12.5 Kwatt total power consumption12.5 Kwatt total power consumption

• Hardware cost: ~ $1MHardware cost: ~ $1M

Unified Digital Processing Unified Digital Processing ArchitectureArchitecture

• Distributed per antenna spectral channel processingDistributed per antenna spectral channel processing

• Multiple reconfigurable backend application Multiple reconfigurable backend application processingprocessing

• Commercial packet switched interconnectCommercial packet switched interconnect

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Why you might not Why you might not want SETI want SETI experiments on the experiments on the SKA:SKA:

Desired SETI SKA Desired SETI SKA ParametersParameters• Wide bandwidth (0.1 to 35 GHz)Wide bandwidth (0.1 to 35 GHz)

• 1 M beams1 M beams

• Wide beams (primary and Wide beams (primary and synthesized)synthesized)

- compact array strongly preferred!!! - compact array strongly preferred!!!

(for both targetted and sky survey)(for both targetted and sky survey)

Seti Haiku

Searching for lifeSearching for lifeAnswers are revealedAnswers are revealedAbout ourselvesAbout ourselves

Paula Cook, Duke UniversityPaula Cook, Duke University

One million earthlingsOne million earthlingsBounded by optimismBounded by optimismLeave their PC’s onLeave their PC’s on

Dan SeidnerDan Seidner

Seti.org

Planetary.org

Seti.berkeley.edu