Okay, I believe the answer to this puzzle is:
A SANTA AT NASA
Why? Well, first of all note that the title is:
The start of a famous palindrome (A man, a plan, a canal... Panama). This made me think that we might be looking for a palindromic answer.
Line 1:
This is a set of multiplication equations, where each colour can be substituted by a number. Ultimately this yields: blue = 0, green = 1, yellow = 2 (since green^2 = green, blue × anything = blue, and the 'Ternary' clue would require the third digit to be 2...).
Line 2:
Two clues are hidden here. 1. Reading the dots and dashes as Morse code gives SPACE. 2. Splitting the coloured segments into four groups of 3 gives the ternary equivalents of 24, 13, 1 and 19, which in A1Z26 spells XMAS.
Line 3:
Two more clues are hidden here. 3. Reading the dots and dashes as Morse code gives 6222. 4. Reading the coloured triplets as ternary gives 1, 14, 20 and 19, which in A1Z26 spells ANTS.
How do we put all this together?
We know from the hints that XMAS and SPACE clue two words in the final answer. Also note that the digits of 6222 sum to 12, which is the total number of letters in the final answer... Is it too big a leap to guess that pairing 6222 with ANTS suggests our answer should have 6 A's, 2 N's, 2 T's and 2 S's?
What can we make from these letters that fits the themes of XMAS (Christmas) and SPACE? 'SANTA' and 'NASA' spring to mind. Slotting these into the appropriate spaces in the (1, 5, 2, 4) answer format and treating it as a palindrome automatically uses the leftover letters and yields the final answer: A SANTA AT NASA!