stuck in the middle, by blue

For dVerse’s prompt: ‘true colours‘.
The challenge was to write from the point of view of a colour…

All across space,
we travel as a pack,
none draws ahead
and none lags back.
But once we meet
an interface
ah, that changes,
how we race.
Blue lags behind
long legged red –
with fewer steps
she surges ahead.
Poor short-legged blue
has turned aside
his greater energy
not helping his stride.
They’re spreading out
with me between.
Who am I?
Yes! I’m green!
I’m in the middle
between red and blue
see, that’s me –
waving at you.
You can’t see me wave?
What do you mean?
I have to be a particle
to be seen!?

Some explanatory notes:
Red light is longer wavelength and lower energy than blue light, but in vacuum all light travels at the same speed, regardless of wavelength. Light travels as a wave, spread out across space – so “pack” is wrong, but easy to rhyme with – apologies to anyone even more pedantic than me (you are out there, aren’t you?). When light reaches an interface, like the atmosphere, it slows down and bends towards the normal (perpendicular) to the interface. Blue slows more than red, and bends more. Light travels as a wave, spread across space, but when light is absorbed, for example by your eyes in the act of seeing, it does so as a particle – all or nothing, and at single point.

Here endeth the lesson… for now.