Why some like Mars being in transit regularly with Earth (5)
I believe the answer is:
taste
'why some like mars being' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.
'transit regularly with earth' is the wordplay.
'regularly' indicates alternate letters (regularly take one letter, leave next etc.).
'with' is a charade indicator (letters next to each other).
'earth' becomes 'E'.
The alternating letters of 'transit' are 'tast'.
'tast'+'e'='TASTE'
'in' is the link.
Can you help me to learn more?
(Other definitions for taste that I've seen before include "Try (food)" , "bit to eat" , "Sample, savour" , "Savour in the mouth" , "Appreciation, discernment" .)