Crossword Genius

Astronomical effect in swing towards Labour? (8)

Ross

I believe the answer is:

redshift

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'astronomical effect in swing towards' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'labour?' is the wordplay.
I cannot quite see how this works, but
'labour?' could be 'red' (red is the colour of the Labour Party) and 'red' is located in the answer.
The remaining letters 'shift' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).

Can you help me to learn more?

(Another definition for redshift that I've seen is " shows evidence of expanding creation!".)

I've seen this clue in The Guardian.
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