what do the gold coins mean next to p lanets

[BananaJane]

I went to earth and looked around and there was nothing to grab

[Khloros]

Gold coins next to a planet means there is an activity there that will either award a powerful or pinnacle item.
It is not necessarily the planet itself, but a activity on it, for example, on earth if you do the hawk moon strike, it awards a pinnical at the end.

[Mez Koo]

Those are powerful or pinnacle gear "challenges" do the objective on that location or activity and get gear that can increase your gear level.

Btw while I don't miss your kinderguardian questions that are easily googled from 2020 I'm glad to see that you survived 2020/2021.