Atmosphere doesn't fade with distance from a body.

[Ezriilc]

The subject says it all.

https://forum.kerbalspaceprogram.com/index.php?/topic/34785-19-hyperedit-v158-july-10-2018-cheat-teleporter-orbitplanet-editor-more/&do=findComment&comment=3800773

[Ezriilc]

From a user:

At Kerbin, the atmosphere gradually thins out as one approaches 70k. This makes it possible for returning spacecraft to enter the atmosphere in a realistic way.

When I use HyperEdit to add an atmosphere to a planet that doesn't natively have one, there is a sudden break to full atmospheric sea level pressure. This causes the spacecraft to suddenly explode at whatever value I entered into HyperEdit. It's suddenly sea level air pressure at reaching that altitude.

You can test this out with any version of HyperEdit / any version of KSP which is appropriate for that version of KSP.
This is a problem for any planet that does not come with an atmosphere.