diff --git a/src/symba/symba_frag_pos.f90 b/src/symba/symba_frag_pos.f90
index 762ccf0d1..8a64454f8 100644
--- a/src/symba/symba_frag_pos.f90
+++ b/src/symba/symba_frag_pos.f90
@@ -655,7 +655,12 @@ function ke_objective_function(v_r_mag, v_r_unit, v_t_mag, v_t_unit, x_frag, m_f
          v_shift(:, i) = v_shift(:, i) + v_t_mag(i) * v_t_unit(:, i) + vcom(:)
          fval = fval + 0.5_DP * m_frag(i) * dot_product(v_shift(:, i), v_shift(:, i))
       end do
-      fval = fval**4
+      if (fval < 0.0_DP) then
+         fval = fval**8
+      else
+         fval = fval**2
+      end if
+
 
       return