# Cutting force (large astronomical body)

1. Oct 16, 2015

### nicholas0211510

I know this is a weird topic but the thought has pestered me lately. How much energy would it take to cut a large astronomical body in half (assuming its a uniform sphere). Let's say a object the size of the moon with the same overall density of the moon.

Say the blade used to cut it is as hard as the strongest matiral known and its 1 mm thick moving at speeds needed to cut through it faster than the gravity can pull the other hemisphere back together (I don't know the exact speed needed) and what formula would associate with calculating this.

Sorry if isn't specific enough I my self am not sure how to explain my question any further, thank you in advanced :)

2. Oct 16, 2015

### phinds

You can't cut it fast enough that the hemispheres won't pull back together. You'd have to use a giant wedge that forced the hemispheres apart and that would cause as much crushing as cutting. Basically I don't think it can be done. Why do you need to know? What's the really issue?

Last edited: Oct 16, 2015
3. Oct 16, 2015

### nicholas0211510

I really have no true reason, it just has been a burning question for some reason, and thank you for clarifying this :)