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Janus Observatory

S8

Ouroboros

Oligarchs take power after an AI catastrophe and extract value while anticipating another collapse. Specialized tools advance as systems knowledge degrades; elites shelter underground and on the Moon while the wider population waits for stability.

Illustration of future S8. Ruined cities, a silenced machine core and scorched ground mark an earlier AI catastrophe. Survivors gather among the ruins while sealed bunkers shelter the elite. Lights brighten and fade in a slow cycle, echoing the scenario’s oscillating growth. The description and data are on this page.

Population in 1,000 years
30 billion≈ 3.8 × the study’s Earth population
Energy used per year
2 thousand EJ a year≈ 3.4 × the study’s Earth energy use2 × 10²¹ joules a year
Trend
Oscillating
Growth rate
No rate given
What is “the study’s Earth”?

The scenario study measures every future against a fixed Earth: 7.9 billion people, each using 75 gigajoules of energy a year (592.5 EJ per year in total). An exajoule (EJ) is a billion billion joules.

The multipliers are rounded and count every world a civilization lives on. The reference is the study’s model, not a measurement of Earth today, and says nothing about how many people a planet can support.

Planetary technosignatures: industrial pollution scaling, p. 12 ↗Table 9 caption and Section 5.1, p. 18 ↗

Source: the scenario study, Table 9 ↗

What this future is like.

How the scenario study describes this civilization. Where it offers more than one option, both are shown. Each line links to the table it came from.

Profile of S8
EconomyScarcityTable 2, p. 5 ↗
PoliticsRule by fewTable 2, p. 5 ↗
SocietyHierarchicalTable 2, p. 5 ↗
Technology and natureThey are one and the same or Technology sits inside natureIn the paper: The biosphere and technosphere are equivalent sets / The technosphere is a proper subset of the biosphereTable 4, p. 7 ↗
Centers of technologyOne centerIn the paper: UnipolarTable 4, p. 7 ↗
How technology developsEvolved and emergentTable 4, p. 7 ↗
Smallest engineering scale1 nm to 1 μmTable 4, p. 7 ↗

What a telescope could see.

Five instruments, from the observing study. “Nothing listed” means the study lists no sign for that instrument—not that this civilization has no technology.

01

Optical space telescope

  • CO2 + NO2
Habitable Worlds Observatory
Reflected light
02

Radio telescope array

Nothing listed for this instrument.

Radio array
Radio signals
03

Infrared telescope array

  • CO2 + CFC-11/12
  • N2O + CH4 + NH3
Large Interferometer for Exoplanets
Thermal glow
04

Sun-as-a-lens telescope

Nothing listed for this instrument.

Solar Gravitational Lens
Resolved surface imaging
05

Visiting space probe

  • large surface features (Earth)
Deep-space probe
Close-up exploration
Source: the observing study, Figure 6 ↗

Marks on each world.

Pollution, night lights, reshaped land, satellites and haze on Earth, the Moon, Mars and Venus, compared with Earth today. Each kind of mark keeps its own units; we don’t squash them onto one scale.

Marks on each world in S8
WorldMarkAmountMeasured asSource
EarthIndustrial pollution7.8abundance relative to Earth 2024Table 6, p. 14 ↗
MoonIndustrial pollution0.00006abundance relative to Earth 2024Table 6, p. 14 ↗
MarsIndustrial pollutionS5 and S6 include artificial greenhouse gases for terraforming Mars.Not givenabundance relative to Earth 2024Table 6, p. 14 ↗
VenusIndustrial pollutionS5 and S6 indicate O2 production and depletion of other constituents for terraforming Venus.Not givenabundance relative to Earth 2024Table 6, p. 14 ↗
EarthAgricultural pollution3abundance relative to Earth 2024Table 6, p. 14 ↗
MoonAgricultural pollutionNot givenabundance relative to Earth 2024Table 6, p. 14 ↗
MarsAgricultural pollutionNot givenabundance relative to Earth 2024Table 6, p. 14 ↗
VenusAgricultural pollutionNot givenabundance relative to Earth 2024Table 6, p. 14 ↗
EarthArtificial illumination0.004intensity relative to Earth 2024Table 6, p. 14 ↗
MoonArtificial illumination1e-7intensity relative to Earth 2024Table 6, p. 14 ↗
MarsArtificial illuminationNot givenintensity relative to Earth 2024Table 6, p. 14 ↗
VenusArtificial illuminationNot givenintensity relative to Earth 2024Table 6, p. 14 ↗
EarthSurface modification0.03fraction of planetary surfaceTable 6, p. 14 ↗
MoonSurface modification0.000003fraction of planetary surfaceTable 6, p. 14 ↗
MarsSurface modificationNot givenfraction of planetary surfaceTable 6, p. 14 ↗
VenusSurface modificationNot givenfraction of planetary surfaceTable 6, p. 14 ↗
EarthSatellite belt2density relative to Earth 2024Table 6, p. 14 ↗
MoonSatellite belt0.001density relative to Earth 2024Table 6, p. 14 ↗
MarsSatellite beltNot givendensity relative to Earth 2024Table 6, p. 14 ↗
VenusSatellite beltNot givendensity relative to Earth 2024Table 6, p. 14 ↗
EarthContaminated aerosol0.4density relative to Earth 2024Table 6, p. 14 ↗
MoonContaminated aerosol0.0002density relative to Earth 2024Table 6, p. 14 ↗
MarsContaminated aerosolNot givendensity relative to Earth 2024Table 6, p. 14 ↗
VenusContaminated aerosolNot givendensity relative to Earth 2024Table 6, p. 14 ↗

Beyond Earth, and over time.

Signs of technology across the Solar System come from the scenario study. Collapse and recovery come from a separate study that simulates each future for 1,000 years.

Signs beyond Earth

  • Radio leakage
  • Optical communication
Table 8, p. 17 ↗

Collapse and recovery

Low-frequency, self-stabilizing oscillations with about two collapses and a high duty cycle.

Time spent active
87% on average
Collapses
About 2 on average
How precise
Approximate, from the paper’s text
Figure 3, p. 9 ↗

The air on this Earth.

The gases and temperature the observing study gives this future’s Earth. Where the paper leaves a value out, we show “Not given” rather than zero.

Show the atmosphere table
Atmosphere of Earth in S8
Gas or propertyValueUnitSource
Mean Temperature296KTable 1, p. 4 ↗
CO21400ppmTable 1, p. 4 ↗
CH44.6ppmTable 1, p. 4 ↗
NOx15ppbTable 1, p. 4 ↗
N2O680ppbTable 1, p. 4 ↗
NH326ppbTable 1, p. 4 ↗
CFC-111.8ppbTable 1, p. 4 ↗
CFC-124.1ppbTable 1, p. 4 ↗
NF319.5pptTable 1, p. 4 ↗
SF686pptTable 1, p. 4 ↗
CF4440pptTable 1, p. 4 ↗
SO2, StratosphericNot givenppbTable 1, p. 4 ↗
Na EmissionNot givenerg s^-1 cm^-2Table 1, p. 4 ↗
Laser Emission, 1.064 umNot givenMWTable 1, p. 4 ↗

Objects from this world.

Stories and objects artists made inside this future. They’re fiction, not evidence. Works whose creators reserve all rights are linked, never copied here.