Planetary · Stars
White dwarf
≈12,700 kmA Sun-like star’s exposed core can pack a star’s mass into a body about Earth’s size.
Planetary ↔ Planetary
Is a white dwarf about the size of Earth?
The comparison is striking because the two diameters are similar while their mass, density and physical nature are radically different.
Linear ratio1.003×
Using the stated linear measurements, Earth is 1.003× White dwarf.
Planetary · Solar system
Earth
12,742 kmOur ocean world, measured by mean diameter — the anchor for familiar planetary comparisons.
The answer
A ratio, an analogy and the definitions behind both.
Using the stated linear measurements, Earth is 1.003× White dwarf.
About 1.003× White dwarf linear spans fit across the selected measurement of Earth.
representative stellar-remnant diameter versus mean diameter
The metre values can be divided as linear spans, but the two entries do not describe identical kinds of boundary.
White dwarf is representative; earth is measured.
Representative, variable and model-dependent values are useful for perspective only when their status remains visible.
Measurement ledger
What exactly was divided?
| Landmark | Value | Measurement | Certainty | Source |
|---|---|---|---|---|
| White dwarf | ≈12,700 km | representative stellar-remnant diameter | Representative | NASA Science ↗ |
| Earth | 12,742 km | mean diameter | Measured | NASA Science ↗ |