Echo is goofy ah space cat that you can find throughout Luna. Interacting with Echo yields a variety of rewards from bytes to a new jet suit, so it's well worth going out of the way to find her. Very important to note that she has a CHANCE to spawn every time you load into the area, so if you don't see her at the right location, enter a room and come back to reload the area.

Echo can be found in the Barrier Facility just above where you repair the ship and next to the cranes for the laser door puzzle.

This one's a bit of a trek because we can only walk, head to the 3rd floor and make your way all the way around to where mission control is. From there, head straight down into the empty dock to find Echo chilling with the janitor.

Probably the trickiest one to find simply because this city is so big and has so many tall buildings. Put on your jet suit from the center plaza and head to top right most section of the map, Echo will be just above the 3 way intersection of the green highway over the water.

Head straight up from the Tycho BBS to find Echo drifting in empty space. There are actually posts on this same BBS that tell you Echo can be found here and provides clues for the other locations as well!

The last location for Echo is in Colony Silica. After putting on your jet suit, head up and to the right of the cafe and the general store, just above a couple sets of crystals to find her.

Having found Echo 5 times you're now all the richer, got a silly new jet suit, and get a nice shiny green star badge for Echo Encounters in your Records page!