Remembering the first expedition

As far as those back on Irth know, the Prometheus was lost with all hands on board somewherein deep space 50 years before the Nostromo left port.

Do we know it's heavily touted? What if it's a secret?

i would say it's like airline crashes of today sure we hear about them but it just happens when terraforming new worlds you are going to have ships crash, disappear and malfunction so the nostromo crew might know a ship named prometheus was lost but who cares, it happens

Space is big. If something were to happen to the Prometheus, no one would ever hear about it. It would just be missing. Heck, it would take years before anyone back home knew anything went wrong.

Else the entire Prometheus expedition is secret. In public it is reported to go left when it actually goes right.

Ships and planes were lost in the Bermuda triangle for over a hundred years. Now they build resorts there and people fly in with barely a thought of those that have been lost. No pun intended.