This is an optional but useful companion product to Interstellar Patrol. It expands on the situations and worlds found there. Note that you're still getting seeds, not fully fleshed-out adventures or worlds. This is good for a low-prep or pickup game.
The plot cards offer a good variety of situations. Each card gives you two brief situations that fit a certain theme, such as Strange Phenomenon or Enemy Action. As an earlier reviewer said, the description font could have been bigger. The adventure fractal icons on the plot cards are unnecessary, so they just take up real estate that could have left room for a bigger font. Each situation description is just a sentence or two, so it's up to you and your group to run with it.
The adventure fractal cards are for those who are following the adventure fractal model described by Ryan Danks. Here's his archived description:
Each adventure fractal card assigns the values +0, +1, +2, and +3 to the adventure's or scene's four skills: combat, diplomacy, exploration, and science. In aggregate, the cards cover every possible combination of skills and values.
The world cards offer good variety. Each card gives the world a skill level, a world aspect (e.g., Well-Established Colony), a story aspect (e.g., Hidden Technologies), a world type, and a name. The world and story aspects and the names are unique to each card. The world type is one of those described briefly in Interstellar Patrol. Apply the world's skill level to the world's denizens and challenges. Invoke the aspects when appropriate, and use them as narrative guidance for the kinds of denizens, locations, things, and events you're likely to encounter.
You can play Interstellar Patrol without the cards, but the cards are a good addition.