Minimal conditions for survival of technological civilizations in the face of stellar evolution

Abstract

The ease of interstellar rocket travel is an issue with implications for the long term fate of our own and other civilizations and for the much-debated number of technological civilizations in the Galaxy. We show that the physical barrier to interstellar travel can be greatly reduced if voyagers are patient, and wait for the close passage of another star. For a representative time of $\sim$1 Gyr, characteristic of the remaining time that Earth will remain habitable, one anticipates a passage of another star within $\sim 1500$~AU. This lowers the travel time for interstellar migration by $\sim$ two orders of magnitude compared with calculated travel times based on distances comparable to average interstellar separations (i.e., $\sim$1 pc) in the solar vicinity. We consider the implications for how long-lived civilizations may respond to stellar evolution, including the case of stars in wide binaries, and the difficulties of identifying systems currently undergoing a relevant close encounter. Assuming that life originates only around G-type stars, but migrates primarily to lower mass hosts when the original system becomes uninhabitable, the fraction of extant technological civilizations that exist as diaspora can be comparable to the fraction that still orbit their original host stars.

arXiv comment9 pages, 0 figures, to appear in the Astronomical Journal

References in corpus (47)

• On the variation of the Initial Mass Function
• Gaia Data Release 2: The astrometric solution
• A Survey of Stellar Families: Multiplicity of Solar-Type Stars
• Habitable Zones Around Main-Sequence Stars: New Estimates
• Stellar Multiplicity
• Prevalence of Earth-size planets orbiting Sun-like stars
• The Occurrence and Mass Distribution of Close-in Super-Earths, Neptunes, and Jupiters
• Terrestrial Planet Occurrence Rates for the Kepler GK Dwarf Sample
• A Re-appraisal of the Habitability of Planets Around M Dwarf Stars
• The HARPS search for southern extra-solar planets XXXIV. Occurrence, mass distribution and orbital properties of super-Earths and Neptune-mass planets
• The White Dwarf Initial-Final Mass Relation for Progenitor Stars From 0.85 to 7.5 M${}_{\odot }$
• Kepler-62: A five-planet system with planets of 1.4 and 1.6 Earth radii in the Habitable Zone
• Occurrence Rates of Planets orbiting FGK Stars: Combining Kepler DR25, Gaia DR2 and Bayesian Inference
• Planetary System Disruption by Galactic Perturbations to Wide Binary Stars
• The Occurrence of Rocky Habitable Zone Planets Around Solar-Like Stars from Kepler Data
• A Statistical Reconstruction of the Planet Population Around Kepler Solar-Type Stars
• Dynamics and Interactions of Binaries and Neutron Stars in Globular Clusters
• The Breakthrough Listen Search for Intelligent Life: 1.1-1.9 GHz observations of 692 Nearby Stars
• Stellar Inventory of the Solar Neighborhood using Gaia DR1
• Influence of Stellar Multiplicity On Planet Formation. II. Planets Are Less Common in Multiple-Star Systems with Separations Smaller than 1500 AU
• The Masses of Population II White Dwarfs
• Synthesizing Exoplanet Demographics from Radial Velocity and Microlensing Surveys, II: The Frequency of Planets Orbiting M Dwarfs
• The Solar Neighborhood XLIV: RECONS Discoveries within 10 Parsecs
• A 1.1 to 1.9 GHz SETI Survey of the Kepler Field: I. A Search for Narrow-band Emission from Select Targets
• Stellar Encounter Rate in Galactic Globular Clusters
• Occurrence Rates of Planets Orbiting M Stars: Applying ABC to Kepler DR25, Gaia DR2, and 2MASS Data
• The Ĝ Infrared Search for Extraterrestrial Civilizations with Large Energy Supplies. I. Background and Justification
• How Much SETI Has Been Done? Finding Needles in the n-Dimensional Cosmic Haystack
• Planets in 47 Tuc
• The Occurrence of Wide-Orbit Planets in Binary Star Systems
• New stellar encounters discovered in the second Gaia data release
• SETI Observations of Exoplanets with the Allen Telescope Array
• A Search for Laser Emission with Megawatt Thresholds from 5600 FGKM Stars
• The stellar Initial Mass Function of the solar neighbourhood revealed by Gaia
• Exocomets: A spectroscopic survey
• The stellar velocity distribution function in the Milky Way galaxy
• Accounting for Multiplicity in Calculating Eta Earth
• The Fermi Paradox and the Aurora Effect: Exo-civilization Settlement, Expansion and Steady States
• Planetary Architectures in Interacting Stellar Environments
• A search for technosignatures from TRAPPIST-1, LHS 1140, and 10 planetary systems in the Kepler field with the Green Bank Telescope at 1.15-1.73 GHz
• Globular Clusters as Cradles of Life and Advanced Civilizations
• Extrasolar Asteroid Mining as Forensic Evidence for Extraterrestrial Intelligence
• 8 in 10 Stars in the Milky Way Bulge Experience Stellar Encounters Within 1000 AU in a Gigayear
• Orbit-superposition models of discrete, incomplete stellar kinematics: application to the Galactic centre
• Characterizing the Chemistry of Planetary Materials Around White Dwarf Stars
• Probing the Survival of Planetary Systems in Globular Clusters with Tidal Disruption Events
• Direct Exoplanet Investigation using Interstellar Space Probes

Cited by in corpus (7)

• The Case for Technosignatures: Why They May Be Abundant, Long-lived, Highly Detectable, and Unambiguous
• Infrared and Optical Detectability of Dyson Spheres at White Dwarf Stars
• Unbound Close Stellar Encounters in the Solar Neighborhood
• Galactic Traversability: A New Concept for Extragalactic SETI
• Galactic settlement of low-mass stars as a resolution to the Fermi paradox
• SETI in 2021
• Stellar encounters in the solar neighbourhood and the special case of GJ~710