Monday night, in a friendly free for all, I ended up with Wonder Man and US Agent side by side, needing Wonder Man to throw an object at someone else. US Agent was on one of his Enhancement clicks. Should Wonder Man have gotten a +1 to the thrown object's damage or not? I paused the game to have time to read through the PAC and rulebook, and I came up with a tentative "No" based on how thrown objects deal their own damage independent of what the throwing characters' damage values are (2 for light, 3 for heavy).

But the question remains! Can you use Enhancement to boost the damage of a thrown object?

Also, what about a Critical Hit? Would a Critical Hit boost the damage of a thrown object?

No. Enhancement affects the damage value of the attacking character, and that is not used when throwing an object.
That affects damage dealt, so it works just fine.

Thanks, Quebbster. That's what I thought! Just making sure!