Earth - Granite, Water, and a Breathable Atmosphere
Origin & Age
Earth is ~4.6 billion years old. Among known worlds, it is unique in sustaining liquid water, active plate tectonics, and vast granite continents—conditions that fostered life, culture, and civilization.
Earth Specs
| Item | Value | Notes |
|---|---|---|
| Age | ~4.6 billion years | — |
| Diameter | 12,742 km | Similar to Venus |
| Mass | 5.97 × 1024 kg | Largest rocky planet |
| Gravity | 1 g | Reference value |
| Mean surface temp. | ~15°C | Global average |
| Atmosphere | ~78% N2, ~21% O2, traces of others | Breathable |
| Can humans move bare-skinned? | Yes | Only planet where this is routine |
| With spacesuit? | Not required | — |
Main Rocks on Earth (Materials View)
| Rock | Key traits | Elsewhere? | Uses (material) | Major sources |
|---|---|---|---|---|
| Granite | Silica-rich intrusive rock; slow-cooled, strong, beautiful crystals | Large continental volumes unique to Earth | Lanterns, monuments, sculptures, gravestones, cladding | Japan (Okazaki, Kagawa), India, Brazil, China |
| Basalt | Dark volcanic rock; forms oceanic crust | Yes (Moon, Mars, Venus) | Aggregates, road base, rock wool | Japan (Fuji, Aso), Hawaii, Iceland |
| Andesite | Intermediate volcanic rock common in arcs | Possible analogs on Venus/Mars | Building stone, masonry | Japan (Izu–Tohoku arcs), Andes |
| Limestone | Biogenic sedimentary rock (corals, shells) | Requires biology; unconfirmed elsewhere | Cement, building stone, sculpture | Japan (Akiyoshidai), Europe, China |
Continental vs. Oceanic Crust
Earth’s surface is a mosaic of two contrasting crusts:
- Continental crust: granite-rich, low density, ~35 km thick, buoyant—forms the continents.
- Oceanic crust: basalt-rich, higher density, ~7 km thick—recycled by subduction.
This coupling powers plate tectonics, continually renewing the surface and concentrating resources essential for civilization.
Why Earth Is Unique
- Granite continents created by water-assisted remelting and recycling.
- Oxygen-rich atmosphere sustained by life.
- Abundant liquid water connecting climate, erosion, and rock cycles.
In the Solar System—and likely even across the Galaxy—this combination is rare.
Environment & Human Activity
Unlike gas giants or airless moons, Earth offers moderate temperatures, a protective atmosphere, and drinkable water. It is the only known world where humans can live and work bare-skinned.
Summary
- Origin: ~4.6 Ga; only world with vast granite continents
- Composition: granite (continents) vs. basalt (oceans)
- Environment: breathable air, liquid water, active plates
- Cultural stage: geology enabled cities, art, and industry
Earth uniquely produces the granite products offered by japanstones.shop.
