Currently my Planetary Tech allows for the 750 defense Planetary Shield and the 450 attack Singularity Minefield.

I'm under the impression that when figuring planet defense the attack and defense are simply added together. If that is the case, is it worthwhile to put in the attack structures or just keep the defensive ones?

A little bit of attack is recommended if you can't completely cloak your planets, but the majority of the att/def structures should be DEFENSE. Here's why... An orbital mass disruption reduces planet attack by 30% while an ion storm charge will only reduce the defense by 15%. Attack strength on a planet is mainly for whacking someone back when they attack you planet, in the hopes that repairs will be too costly for them to continue. With those two artifacts, they can nerf the planet's attack more so than the defense, so when it comes to the actual invasion, defense will maintain a higher stat than attack will.

attack is worth less than defense when invading, its defense + attack * 0.6.

generally best to stick to pure defense, if thats your highest tech, its also harder to reduce, if your worried about sabs, a couple of population modules can reduce the scan of a sab disabling an attack/defense

Don't know where you got that formula, but you shouldn't be passing it on as it is completely meaningless.

This guy is who????

Aw c'mon Chakotay.... You know who I am...

Darth's right... your equation is way off.... could you tell me where you're getting this info so we can make sure they learn the right equation...

every point of regular planet defense, every point of planet invasion defense, and every point of planet attack are weighted equally during an invasion

player invasion attack / (3x sum of all planet defense and invasion defense and planet attack after buffs and legion bonus) = chance to invade

note: even invasion defense gets legion bonuses... and the invasion-only portion of player invasion attack does not get your % buffs applied to it....
The equation has been examined over and over again... your atk*0.6 must've been from long before we locked in on the equation that gives 100% accurate results