Interstellar · Distance
One light-year
9.461 trillion kmThe standard interstellar distance unit: how far light travels in one year through vacuum.
Interstellar ↔ Interstellar
How many light-years away is Proxima Centauri?
Compare a defined distance unit with the measured separation to the nearest star beyond the Sun.
Linear ratio4.239×
Distance to Proxima Centauri is 4.239× the linear separation represented by One light-year.
Interstellar · Distance
Distance to Proxima Centauri
≈4.24 light-yearsThe gap between the Sun and the nearest known star beyond it.
The answer
A ratio, an analogy and the definitions behind both.
Distance to Proxima Centauri is 4.239× the linear separation represented by One light-year.
About 4.239× One light-year linear spans fit across the selected measurement of Distance to Proxima Centauri.
distance light travels in one Julian year versus Sun-to-star distance
The metre values can be divided as linear spans, but the two entries do not describe identical kinds of boundary.
One light-year is defined; distance to Proxima Centauri 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 |
|---|---|---|---|---|
| One light-year | 9.461 trillion km | distance light travels in one Julian year | Defined | NASA Science ↗ |
| Distance to Proxima Centauri | ≈4.24 light-years | Sun-to-star distance | Measured | NASA Science ↗ |