Spiritual ancestors of Prospector.

[StarshipEngineer]

... you'll probably know some of them.

Star Control II
If you don't know it, you're missing one of the most exciting, memorable and funny "explore the galaxy, loot planets, talk to (and shoot) all kinds of aliens" games out there.

Starflight I and II
Ah, the classics. They probably started the whole genre. Probably not worth playing nowadays, but well worth remembering.

Star Command
This one's a bit obscure. It was made by the now-defunct company SSI and focused on space combat and tactical combat (you could even board, and then tow, enemy spaceships if they were the last enemy ship remaining), but you could also do quite a bit of exploration and looting. Leveling up the crew and earning enough money to repeatedly upgrade and change your spaceship was a big part of the game, too.

[HunterZ]

The Starflight games are worth playing if you can appreciate games from its era. Other than the graphics being extremely low-res, the combat being CPU speed dependent, and the save system being anachronistic it hasn't aged too terribly (and has good plots and exploration).

[d12]

[HunterZ]

Interestingly, the planet terrain maps are actually all generated via a fixed random number seed, so every planet is different but each planet is the same across game sessions. Most non-terrain features (minerals, creatures, ruins, etc.) are randomly generated on the fly, though, so exploration doesn't get too boring.

Starlight was one of the first commercial PC games that I owned, having received it for Christmas around 1987 when I was only around 9 years old. I didn't manage to get far into the game until the mid-90s, but I thought it was the coolest thing ever (and even bought and played the sequel a bunch at one point). I consider the series to be one of my favorites, and I still have the boxes, disks, manuals, maps, etc. for both games a quarter century later.

I was tickled to see how strongly the first Mass Effect game was inspired by Starflight, from navigating the planets in a star system right down to exploring planet surfaces in a terrain vehicle and collecting minerals. I enjoyed ME2 quite a bit less due to the fact that they replaced the surface exploration with an extremely boring and tedious probe launching minigame. I just recently started playing ME3, and it seems to have almost completely done away with exploring planets as a side activity, which I find even more disappointing.

It should also be mentioned that Star Control 2 was heavily influenced by Starflight.

[Happy Corner]

Magellan has acknowledged his debt to Starflight on a few occasions now. And of course, at least a couple other roguelikes now have a debt to HIM...

I really hated the planet exploration in Mass Effect 1. The vehicle's controls were so clunky and you had to cover so much ground between discoveries... some of which weren't ever shown on the minimap, so completists actually had to wander the WHOLE planet like this.

At least in Prospector (and presumably in Starflight), the ground is usually littered with things worth collecting. And even when the terrain made it a challenge to get around, it's more like a puzzle than "Oh for the love of the Flying Spaghetti Monster! Can't this piece of shit move any faster?! Why can't I just go back to my fucking spaceship and have it DROP me off next to the anomaly? ARGH!" You can do the latter in Prospector, too...