Boating: Since what rubble there is to stand on out there doesn't have any freestanding water, this is a fairly pointless skill to take.
Driving: Other than the occasional buggy for travelling across one of the relatively few planetoids, there's not much call for this skill.
Lockpicking: Virtually all locks nowadays are of the electronic variety. Therefore, Lockpicking is linked to Smarts rather than Agility.
Riding: Not only is there nothing to ride, there's nowhere to ride it.
Survival: Normally, this skill is geared towards wilderness environments. But since those don't exist anymore, Survival is used for scrounging in old space stations and abandoned starships for any useful items.
Swimming: As mentioned above, there is no freestanding water to swim in. Not even swimming pools exist since it would be considered wasteful in the extreme to use water in such a frivilous manner.
Tracking: The days of tracking by following bits of disturbed ground are long gone. Nowadays, Tracking primarily involves the use of sensory equipment for such tasks as pinpointing a ship's vector as it entered Hyperspace to determine its exit point as well as other more high-tech forms of tracking. This skill can also be used to employ sensory countermeasures to thwart such attempts.
Alchemy (Spirit)
This arcane skill allows the creation of various magical items like potions, power point batteries, enchanted weapons, and spell locks. It is only available to the Alchemist Arcane Background.
Astrogation (Smarts)
This skill is necessary to plot a course through both normal space and Hyperspace. If a working navcomputer isn't available, rolls are at -2.
Gunnery (Smarts)
Firing a ship mounted weapon is a lot different from shooting a laser pistol. This skill handles the use of all such weapons, ranging from the laser cannons on a fighter to the big guns on a dreadnaught.
Sorcery (Spirit)
This arcane skill is needed for the casting of spells. Only Arcane Backgrounds with any spells to choose from may take this skill.
Summoning (Spirit)
This arcane skill can be used to summon, control, banish, and exorcise spirit beings. The user's Arcane Background determines what kind of spirits they may use this skill on and for what purpose.