Redshift to million light-years
Type a value in z to get it in Mly instantly.
That's 4.3× as distant as the Coma cluster, while the nearest quasar is 1.58× further. Light from it arrives about 10% longer in wavelength.
What it means
How far is that?
Distances use a simple Hubble law at 70 km/s per Mpc, which is only a good guide for small z. Beyond about z = 0.1 the real answer depends on the expansion history.
The math
How to convert z to Mly
Redshift is a stretch: 1 + z = observed ÷ emitted wavelength. Speed follows relativistically, v = c × ((1+z)² − 1) ÷ ((1+z)² + 1), and distance from v ÷ H₀ at 70 km/s per Mpc.
Example: 0.1 z = 1,327.32 Mly.
Every unit
Your redshift in every unit
Tables
z to Mly conversion table
| z | Mly |
|---|---|
| 0.001 z | 13.9615 Mly |
| 0.01 z | 138.986 Mly |
| 0.05 z | 680.982 Mly |
| 0.1 z | 1,327.32 Mly |
| 0.5 z | 5,372.48 Mly |
| 1 z | 8,381.07 Mly |
| 2 z | 11,174.8 Mly |
| 3 z | 12,325.1 Mly |
| 5 z | 13,213.4 Mly |
| 7 z | 13,538.6 Mly |
| 11 z | 13,775.8 Mly |
Mly to z conversion table
| Mly | z |
|---|---|
| 0.001 Mly | 7.159×10⁻⁸ z |
| 0.01 Mly | 7.159×10⁻⁷ z |
| 0.05 Mly | 3.58×10⁻⁶ z |
| 0.1 Mly | 7.159×10⁻⁶ z |
| 0.5 Mly | 3.58×10⁻⁵ z |
| 1 Mly | 7.159×10⁻⁵ z |
| 2 Mly | 0.00014319 z |
| 3 Mly | 0.000214793 z |
| 5 Mly | 0.000358014 z |
| 7 Mly | 0.000501255 z |
| 11 Mly | 0.0007878 z |
Quick answers
Quick answers
- How many Mly is 1 z?
- 1 z is 8,381.07 Mly.
- How many Mly is 10 z?
- 10 z is 13,739.5 Mly.
- How many Mly is 0.1 z?
- 0.1 z is 1,327.32 Mly.
The units
About these units
Redshift (z)
The fractional stretch in wavelength, the number astronomers actually publish.
Million light-years (Mly)
The same distance in light-years, which reads more naturally.
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