it looks like the effect you get from the amp station when it changes factions... But, uh, I have no idea what it's doing there... looks like a glitch
I filed an ingame bug report about this 2 weeks ago. Basically the particle effect doesn't stop rendering after you take the installation. It happens with biolabs aswell, the top of the tower keeps being lit up for many minutes if it ever terminates. The amp station top has this too, but now the bug has started earlier in the animation it seems.
Orbital strikes have been a secret priority (due to popular demand in the roadmap) and now make their comeback!
I would stay away, last time I saw that thing a butt-naked body builder appeared and stole my clothes, my boots and my motor cycle.
I just played for 1 hour and I saw almost 20 of these during that time. 5 around a single tower. That tower, howevere, was uncappable (buggy). So not just happen after capping.