Rotate towards target doesn't work properly (Quaternion.lerp)

Hello,

I wrote a simple "Rotate towards target" script and was testing it but for some reason the object that I rotate ends up upside down.

Here is the code: (javascript)

 #pragma strict
 
 var target : Transform;
 var strength = .5;
 var targetRotation : Quaternion;
 var str : float;
  
 function Update () {
    targetRotation = Quaternion.LookRotation (target.position - transform.position);
    str = Mathf.Min (strength * Time.deltaTime, 1);
    transform.rotation = Quaternion.Lerp (transform.rotation, targetRotation, str);
 }

and here is the picture of what is going wrong:

The ship needs to rotate with the front towards the planet in the background but ends up with the front down. I already changed the pivot/origin point in my 3d software (blender) but that doesn't change a thing...

How do I fix this?

Thanks in advance,

Gijs