It has a low point in the sky (4)
I believe the answer is:
moon
'point in the sky' is the definition.
'moon' can be an answer for 'point' (I have seen 'low point' mean 'moon' so perhaps 'point' could also mean 'moon'). I am not sure about the 'in the sky' bit.
'it has a low' is the wordplay.
'it' becomes 'n' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'has' means one lot of letters go next to another.
'a low' becomes 'moo' (both can mean to make the noise of a cow).
'n' put after 'moo' is 'MOON'.
Can you help me to learn more?
(Other definitions for moon that I've seen before include "The Earth's natural satellite" , "low point" , "Heavenly body < exemplified in Titania?" , "Expose one's buttocks" , "Phoebe" .)