The California Nebula is a long cloud of glowing hydrogen in Perseus, named for its outline, ionised by the hot star Menkib (Xi Persei) beside it.
At a glance
| type | nebula |
|---|---|
| distance from the Sun | 1,420 light-years (436 pc) |
| its light left it | 1,420 years ago |
| size in the piece | about 55 light-years acrossmodel |
Read off the piece’s own catalogue, the same values it draws with. Model marks a property of the piece’s galaxy model rather than a measurement.
About California Nebula
The nebula is an emission nebula: hydrogen gas made to glow red by the ultraviolet light of Menkib, a hot, massive star close to it in space. Long-exposure photographs show a long ribbon whose shape recalls the American state.
Large on the sky but faint, it is hard to see by eye even through a telescope; a filter that passes only the hydrogen light helps. Menkib is a runaway star moving fast through space, so the nebula is lit by a passing star rather than by one born in the cloud.
What you see in the piece
In visible light it is a faint red ribbon near Menkib; its colour is the glow of hydrogen, the red that ionised gas gives off.
Questions
How far away is the California Nebula?
The California Nebula is about 1,420 light-years (436 pc) from the Sun.
What makes the California Nebula glow?
Ultraviolet light from the hot star Menkib (Xi Persei) ionises its hydrogen, which glows red as it recombines.