As a spook ship I suppose Glomar Explorer's security might have been a bit tighter than on Glomar Challenger.
I went down to look at that when it was in Leith, and, thinking it was open to the public, went up the gangplank and wandered around a bit. Didn't seem to be anyone about, but eventually I bumped into this girl with a clipboard.
"Oh hello, We're in the wardroom. Come along and get yourself a coffee. We'll start in 5 minutes"
Ok, I thought, I could do with a coffee.
Room had maybe 20 people in it who didn't seem to know each other. Can't remember but I don't think I spoke to anyone. Eventually a geezer turned up and welcomed us on board, and asked us to introduce ourselves, so I did. "Ed Lithgow, Edinburgh University". No alarms or sirens. Then, after a brief intro to the ship and the up-coming research cruise they started talking about cabin allocations and apologized for me not being on the list yet, "Its often out of date" and I thought I'd better own up.
Always rather regretted that, though. It would have been interesting to see how long I could get away with it. The ship sailed that evening and it might have been a while before they could put me ashore.
You never know, I might have turned out a talented oceanographer.
OTOH, if that was a spook ship too I might have been buried at sea.