The best way to describe the behavior I am seeing is z-fighting with the star sector background and the rest of the drawn elements including the UI. Once it begins to happen it does not stop until I restart the game. Not sure if this happens in the intergalactic travel, and this doesn't appear to happen with the combat background.
Resolution doesn't seem to affect it, tried it with 1600x900, 1920x1080, and 3200x1800
I've tried other Java games like Minecraft and Rise to Ruin and was unable to observe similar behavior.
Using the 64bit Java 7 because that was easier than hunting down the required 32-bit libraries for Ubuntu 17.04
Running on an Intel i7-7500U and Intel HD Graphics 620 with driver version i915.
Spoiler
0 [main] INFO com.fs.starfarer.StarfarerLauncher - Starting Starsector 0.8a-RC19 launcher
1 [main] INFO com.fs.starfarer.StarfarerLauncher - Running in $HOME/Downloads/starsector
1 [main] INFO com.fs.starfarer.StarfarerLauncher - OS: Linux 4.10.0-21-generic
1 [main] INFO com.fs.starfarer.StarfarerLauncher - Java version: 1.7.0_80 (64-bit)
32 [main] INFO com.fs.starfarer.settings.StarfarerSettings - Loading settings
39 [main] INFO com.fs.starfarer.loading.LoadingUtils - Loading JSON from [ABSOLUTE_AND_CWD: null (data/config/settings.json)]
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 320x240, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 400x300, 113Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 400x300, 121Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 512x384, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 576x432, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 640x480, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 640x480, 60Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 640x512, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 680x384, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 700x525, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 720x450, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 800x512, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 800x600, 56Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 800x600, 120Hz, 24bpp
205 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 800x600, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 840x525, 120Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 896x672, 120Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 928x696, 120Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 960x720, 120Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 960x600, 120Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 960x540, 120Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1024x768, 120Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1024x768, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1152x864, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1280x1024, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1280x960, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1360x768, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1400x1050, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1440x900, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1600x1200, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1600x900, 60Hz, 24bpp
206 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1600x1024, 60Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1680x1050, 60Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1792x1344, 60Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1856x1392, 60Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1920x1200, 60Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1920x1080, 60Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 1920x1440, 60Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 2048x1536, 60Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 3200x1800, 48Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Found display mode: 3200x1800, 60Hz, 24bpp
207 [main] INFO com.fs.starfarer.launcher.opengl.GLLauncher - Assuming native monitor resolution is 3200x1800
274 [Thread-3] INFO com.fs.graphics.for - Using refresh rate:60
499 [Thread-3] INFO com.fs.graphics.TextureLoader - Cleaned buffer for texture graphics/ui/launcher_bg.jpg (using cast)