Bounty hunter respawn jetpack

Ok like many others I've failed or didn't have the opportunity to scan jetpack guy. . Now that being said I've cleared the game only missing that one scan. I've gone threw every planet fought at every bounty hunter spawn location. 

Now do bounty hunter respawn after killing them at a certain location? Or once you kill them that spot no longer respawns a bounty hunter. 

Fun game I like platinuming games to get the most out of them but I'm just curious if I'm out of luck or what . Not mad just be nice to no for sure