Instead of being thrown back, you'll get sucked in if you put a negative value in impulseForce.
datablock ExplosionData(rocketExplosion)
{
//explosionShape = "";
explosionShape = "./shapes/explosionSphere1.dts";
soundProfile = rocketExplodeSound;
lifeTimeMS = 150;
particleEmitter = rocketExplosionEmitter;
particleDensity = 10;
particleRadius = 0.2;
emitter[0] = rocketExplosionRingEmitter;
faceViewer = true;
explosionScale = "1 1 1";
shakeCamera = true;
camShakeFreq = "10.0 11.0 10.0";
camShakeAmp = "3.0 10.0 3.0";
camShakeDuration = 0.5;
camShakeRadius = 20.0;
// Dynamic light
lightStartRadius = 5;
lightEndRadius = 20;
lightStartColor = "1 1 1 1";
lightEndColor = "0 0 0 0";
damageRadius = 3;
radiusDamage = 100;
impulseRadius = 6;
impulseForce = 4000; //Make this a negative value, example: -4000 instead of 4000.
};