Interstellar Spaceprobes and. Encounters with Extraterrestrial. Intelligence.
Stephen Baxter, BIS. NAM 2013. St Andrews, Jul 2013. Ref: JBIS 66, 51-‐60,
2013.
Interstellar Spaceprobes and Encounters with Extraterrestrial Intelligence Stephen Baxter, BIS NAM 2013 St Andrews, Jul 2013 Ref: JBIS 66, 51-‐60, 2013.
Roadmap: How could (and should) we prepare a general-‐purpose interstellar probe for the possibility of the detec=on of (and/or contact with) ETI (extraterrestrial intelligence) at the target system? • Background and assumpFons • DetecFon by probe of ETI • ... Or of probe by ETI • OpFons aNer detecFon / contact • Policies
About me...
• Sf
About me...
• Sf • Project Icarus (BIS) – successor to Project Daedalus (1970s)
About me...
• Sf • Project Icarus • SETI – Post-‐detecFon Task Group
Spaceprobes and ETI -‐ Precedents:
• Voyager and Pioneer • Daedalus
Precedent: Greg Bear, Queen of Angels, 1990 -‐ A smart interstellar probe
Precedent: Greg Bear, Queen of Angels, 1990
Precedent: Greg Bear, Queen of Angels, 1990 • Smart AI • Formula=on • Detec=on • Follow-‐up inves=ga=on • Interpreta=on • Contact ...
AssumpFons • ETI exists in target system
AssumpFons • ETI exists in target system AND • ETI not previously detected from Earth
AssumpFons • ETI exists in target system AND • ETI not previously detected from Earth AND • ETI detectable by probe
AssumpFons • • • •
ETI exists in target system AND ETI not previously detected from Earth AND ETI detectable by probe ... OR probe detectable by ETI
Examples:
• Dolphin philosophers
Examples:
• Dolphin philosophers • Pre-‐detectable-‐tech civilisaFons
Examples:
• Dolphin philosophers • Pre-‐detectable-‐tech civilisaFons • Post-‐detectable-‐tech civilisaFons
Detec=on of ETI is a low-‐probability, high-‐impact event:
Detec=on of ETI is a low-‐probability, high-‐impact event: • Enhance probe design rather than dictate it
Detec=on of ETI is a low-‐probability, high-‐impact event: • Enhance probe design rather than dictate it • Moore’s Law – advanced AI assumed
Detec=on of ETI is a low-‐probability, high-‐impact event: • Enhance probe design rather than dictate it • Moore’s Law – advanced AI assumed • Add soNware analysis suites
Could a probe detect ETI? • ElectromagneFc signals • Evidence on planets • Spacebound artefacts / acFviFes
Detec=on: EM Signals • Earth leakage – Arecibo = 0.81 ly (L. Scheffer, ‘Aliens Can Watch “I Love Lucy”’, Contact in Context 2 (1), 2004)
Detec=on: EM Signals • Earth leakage – Arecibo = 0.81 ly • Arecibo d~300m, Daedalus d~40m
Detec=on: EM Signals • Earth leakage – Arecibo = 0.81 ly • Arecibo d~300m, Daedalus d~40m • Detectability ~0.1 ly = 6800AU
Detec=on: EM Signals • Earth leakage – Arecibo = 0.81 ly • Arecibo d~300m, Daedalus d~40m • Detectability ~0.1 ly = 6800AU • Add signal analysis suite to comms, radio astronomy
Detec=on: Planetary features • Atmospheric analysis • City lights • Structures incl archaeological traces
Detec=on: Surface features • StaFsFcal classificaFon algorithms applied to satellite data
Detec=on: Surface features • StaFsFcal classificaFon algorithms applied to satellite data • SyntheFc Aperture Radar (SAR), Polarimetric SAR
Detec=on: Surface features • StaFsFcal classificaFon algorithms applied to satellite data • SyntheFc Aperture Radar (SAR), Polarimetric SAR • DecomposiFon algorithms • M.J. Carlojo, JBIS 60, pp28-‐38, 2007.
Detec=on: Surface features • StaFsFcal classificaFon algorithms applied to satellite data • SyntheFc Aperture Radar (SAR), Polarimetric SAR • DecomposiFon algorithms • Add detec=on algorithms to back up sensor suite
Detec=on: Spacebound artefacts / ac=vi=es • Points of stability: Lagrange points, synchronous orbit
Detec=on: Spacebound artefacts / ac=vi=es • Points of stability: Lagrange points, synchronous orbit • Resource-‐rich regions: asteroid belt, Kuiper belt
Detec=on: Spacebound artefacts / ac=vi=es • Points of stability: Lagrange points, synchronous orbit • Resource-‐rich regions: asteroid belt, Kuiper belt • Add searches for artefacts, infra-‐red hotspots
Could a probe detect ETI? Key conclusion: • DetecFon is possible... • But late in mission • Local decision-‐making essenFal
Could ETI detect the probe? • Probe passive (orbiFng) • Probe under power (launch, deceleraFon) • Probe cruising (0.1c?)
Visibility: probe passive • Artefact searches • Spaceguard • NEAT (JPL) • Bell Aerospace Near Earth Object Survey spacecraN -‐ objects >140m
Visibility: probe under power • AnFmajer rocket: opFcal, ~100ly • Magsail: radio, ~100ly • Fusion rocket: X-‐rays, ~1ly (Zubrin, JBIS 49, pp297-‐302, 1996)
Visibility: lightsails
Visibility: cruising • Bow shock in ISM: ~10ly G. Benford, ‘Bow shock’, Jim Baen’s Universe, June 2006
Could ETI detect the probe? • Tenta=ve Conclusion: If they exist, they may well see us.
OpFons on DetecFon • Science • Contact possibiliFes • Security implicaFons
Post-‐detec=on: science • Signal analysis (J. Ellioj, IAC -‐08 -‐A4.2.5, 2008.)
• Archaeological analysis • Report back
Post-‐detec=on: aIempt contact • Plaques and records
Post-‐detec=on: aIempt contact • Plaques and records • Reflect ETI signals D. Lunan, Man and the Stars, 1974.
Post-‐detec=on: security implica=ons
Post-‐detec=on: security implica=ons
Post-‐detec=on: security implica=ons • J. Diamond, The Third Chimpanzee, 1992 • Pascalian wagers (M. Rees, Our Final Century, 2003.)
Security op=ons • Stealth propulsion, trajectory • Offer no threat (lasers, appearance of KE weapons) • No reply • No maps! • Self destrucFon
Pre-‐launch policy opFons:
Model: The First SETI Protocol: • ‘DeclaraFon of Principles Concerning AcFviFes Following the DetecFon of Extraterrestrial Intelligence’ (M. Michaud and J. Tarter, eds (1990), special issue of Acta Astronau=ca: SETI Post Detec=on Protocol, v21 no 2.)
First SETI Protocol: Content – • ScienFfic responsibility • Responsible reporFng to authoriFes, public • Respond only on consensual basis • Manage event for benefit of all mankind • Duty not to imperil mankind
Towards a probe / ETI protocol? • First SETI Protocol as precedent: – Developed by concerned individuals – Agreement between researchers, insFtuFons – ScienFfic responsibility – Transparency of process – Duty to share benefits – Duty not to imperil mankind
Conclusion:
Conclusion: • Low probability, high impact – remiss not to look
Conclusion: • Low probability, high impact – remiss not to look • Design studies: include minimal ETI detecFon capability
Conclusion: • Low probability, high impact – remiss not to look • Design studies: include minimal ETI detecFon capability • Before launch: policy extension discussions in SETI community and beyond
Conclusion: • Low probability, high impact – remiss not to look • Design studies: include minimal ETI detecFon capability • Before launch: policy extension discussions in SETI community and beyond • Above all...
...Be prepared!
