Space is unimaginably vast – on a galactic scale, stars are little wisps of hydrogen and gas giants are just specks of matter. If ships travelled through the whole of the space in a system, they would never encounter each other.
However, spacecraft tend to crowd to just a few places in any given system, such as the hundred diameter jump limit of colonised worlds, industrial belts in orbit, and gas giants and settled moons. Outside of these regions, the chance of an encounter is negligible.
To generate a random encounter, roll 1D every day.
On a 6, the ship has encountered something -
roll D66 on the Space Encounters table,
applying the following DMs to the first digit of the D66 only
(thus, Settled Space has a range of 21-76, and Wild Space has a range of 01-56).
<aside>
🎲 Highport (DM+3): The space near an orbital starport
High-Traffic Space (DM+2): The space near an industrial world with a high-class starport.
Settled Space (DM+1): Most core worlds in settled or colonised space.
Border Systems (DM+0): Outlying worlds near the border, such as the Spinward Marches.
Wild Space (DM-1): Amber or Red worlds.
Empty Space (DM-4): Untravelled space or unexplored systems.
</aside>
it is dumb that this doesn't take even jump hop points into account - if you had two systems with class A starports with an empty hex between them, every jump 1 ship would have to stop there - there'd be people dropping in and out all day long - a pirate laying in wait could just sit and let them come to him
cf.