Thor rants about celestial navigation point (9)

I believe the answer is:

northstar

I'm a little stuck... Click here to teach me more about this clue!

'celestial navigation point' is the definition.
I know nothing about this answer so I cannot tell whether it can be defined by this definition.

'thor rants about' is the wordplay.
'about' indicates anagramming the letters.
'thor'+'rants'='thorrants'
'thorrants' anagrammed gives 'NORTHSTAR'.

Can you help me to learn more?

I've seen this clue in The Daily Express.

Want a hint initially instead of a full solution? Install my app