Exhibit Codex
Earth
Explore Earth’s history, reconstructed continents, modern geography, and the layers beneath the surface.
Open interactive exhibit ↗About this exhibit
A planet with 4.54 billion years of history
Physical profile · seven measurements
- Mean radius
- 6,371.0084 km
- Mass
- 5.97217 ×10²⁴ kg
- Bulk density
- 5.5134 g/cm³
- Sidereal rotation
- 0.99726968 Earth days
- Sidereal orbit
- 1.0000174 Earth years
- Equatorial gravity
- 9.8 m/s²
- Escape speed
- 11.19 km/s
Present-day reference values, rounded from JPL Solar System Dynamics. These are not reconstructed ancient measurements. Gas-giant gravity refers to a reference atmospheric level, not solid ground. Sidereal rotation differs from the solar day.
Reference and coverage
Present-day NASA Blue Marble imagery and Natural Earth geography share one globe with dated historical and paleogeographic reconstructions. Historical borders are snapshots, not annual surveys. Early Earth surfaces are conceptual. Time scaling, surface selection and interior layers belong to this same exhibit.
Available layers
- Atmosphere
- Crust
- Mantle
- Outer core
- Inner core
Planetary record
A connected planet
Liquid oceans, atmosphere, ice, rocks and life exchange matter and energy. Plate motion builds mountains and recycles crust; erosion and sedimentation continually reshape the surface.
Inside Earth
A thin rocky crust overlies a solid mantle that deforms slowly over geological time. A liquid iron-rich outer core surrounds a solid inner core. Moving conductive fluid helps generate the magnetic field.
Read the globe
Select a country, island or ocean. Recent years have annual statistical records where available. Historical political and cultural regions use dated map snapshots. Geological land and ocean selections use reconstructed terrain. Earlier surface patterns are illustrations where geography is unknown.
Time in this exhibit
4.54 billion years ago · Earth forms
Rock and metal accrete into a young planet. Impacts and differentiation release tremendous heat.
Illustrative early-Earth state; surface geography is unknown.
4.5 billion years ago · A molten world
Large impacts repeatedly melt portions of the young Earth. The Moon forms early in this history.
Schematic magma-ocean appearance; timing and duration remain under study.
4.4 billion years ago · Early oceans
Ancient zircons suggest liquid water may already have interacted with crust. A continuous global ocean is an interpretation.
Illustration, not a reconstructed geographic map.
3.5 billion years ago · Early life
Microbial life leaves evidence in ancient rocks. Life is still predominantly microscopic.
Illustrative ocean and crust; no known continental reconstruction at this date.
2.4 billion years ago · Oxygen rises
Atmospheric oxygen increases during the Great Oxidation Event, transforming the chemistry of the planet.
Conceptual surface state. Oxygen is described in the record, not directly measured by this globe.
540 million years ago · Cambrian seas
Marine animal life diversifies. Large shallow seas cover parts of the continents.
PALEOMAP elevation reconstruction at 540 Ma; terrain colors are museum interpretation.
250 million years ago · Pangaea
Most major continental landmasses are joined in Pangaea, surrounded by the vast Panthalassa ocean.
PALEOMAP reconstruction at 250 Ma.
150 million years ago · Age of dinosaurs
Pangaea has begun breaking apart. Dinosaurs occupy varied landscapes as new oceans open.
PALEOMAP reconstruction at 150 Ma.
65 million years ago · After the impact
The end-Cretaceous extinction occurred about 66 million years ago. This view shows the following interval.
PALEOMAP reconstruction at 65 Ma; no impact simulation.
21,000 years ago · Ice age
At the Last Glacial Maximum, large ice sheets covered much of northern North America and Eurasia; sea level was lower.
Modern geography with schematic ice coverage; not a paleo-shoreline reconstruction.
9,974 BCE · Human expansion
At the end of the last ice age, human communities inhabit many regions. Agriculture develops independently in several places.
Political and cultural boundaries use available dated snapshots. Gaps and uncertain boundaries are identified in the geographic record.
Present · Our living planet
An ocean world with a nitrogen-rich atmosphere, diverse ecosystems, and a surface continually reshaped by plate tectonics.
NASA Blue Marble observed mosaic. Modern boundaries: Natural Earth 1:10m.
Read the detailed records
Open the full exhibit Codex for individual structure records and time-specific information. The Credits page lists source creators, licenses and adaptations.