The Earthlings enter the vent from the outside at ground level and walk only a very short distance on one level: when they emerge into the laboratory they are at tabletop level. The lab can be seen to be at ground level when the SID guard shows up with Dan and Steve.
50-year technology gap: Very fast (possibly FTL) spaceships and a working knowledge of planets outside of their own system
The Giants are specifically interested in exploring Mercury and Venus, as well as Earth. Don't they have any planets in their own system?
Within walking distance: a government laboratory
Mark: I guess the giants are just like us. Some of them can be trusted, and some can't.
S 2 : Ep 25
Aired 3/22/70 (50:47)
S 2 : Ep 24
Aired 3/8/70 (50:54)
S 2 : Ep 23
Aired 3/1/70 (50:53)
S 2 : Ep 22
Aired 2/22/70 (50:53)
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