Space explorers start to like this type of voice (5)
I believe the answer is:
nasal
'type of voice' is the definition.
'nasal' can be an answer for 'voice' (thesaurus). I'm unsure of the 'type of' bit.
'space explorers start to like' is the wordplay.
'space explorers' becomes 'nasa' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'start to' says to take the initial letters.
The initial letter of 'like' is 'l'.
'nasa'+'l'='NASAL'
'this' acts as a link.
Can you help me to learn more?
(Other definitions for nasal that I've seen before include "To do with nose, say sound" , "Sniffer's" , "Relating to one's hooter" , "Relating to the nose" , "front piece of helmet" .)