static shale
In the images below, you can see at the end of the description a "reach Generator rank 3/6". This is not present in any other achievement. In the Pulsar achievements, this text is directly after the full stop or the exclamation, no space after them, just direct the text.
plucky ivy
It appears that probably for the achievement Messier 1, the text in the body of the achievement ends with a space, so the String "Reach Crab Pulsar Rank 6" is being added after that, as opposed to the others
static shale
I just realized it says "reach crab rank 6" for the messier 1 achievement
plucky ivy
Oh shit the strings are all different
"Reach Crab Pulsar Rank 6"
"Reach Crab Pulsar Rank 3"
"Reach Crab Rank 6"
The "Rank "+x is definitely it's own String, so it's just adding "Reach " + name of generator + rank bit I just mentioned. Maybe "Pulsar" is its own String segment or was somehow removed with substring methods from the description?