Frank wrote:

I actually still have "Disappearance on Aramat" in a box somewhere; it only
had the mainworld, not a subsector map IIRC.  The mention of it being "half
a sector coreward" of the Imperium is on the back cover, and the Wiki page
says it is near a rift somewhere.  The subsector is named "the Precipice
subsector".  Goodness knows where it was meant to fit; the company that
published it under license (Grenadier) seemed to want to make it fairly
non-specific.

Now this is an intriguing comment. My back cover says nothing of the sort. Are there two different versions?

The entire text - all white text on black - on the back cover of my copy of Disappearance on Aramat is:

"The x-boat message from a group of archeologists on Aramat is long overdue. The planet is seemingly peaceful and uninhabited. What could have happened? A worried father has now hired you to find out what happened to his archaeologist daughter. Can you solve the mystery of the disappearance on Aramat?"

And then down at the bottom:

"A Traveller adventure for 4-6 players." (With Traveller picked out in red)

While I'm here, I should say I've long had a certain fondness for the artwork in the book.