Was asteroid belt a destroyed planet?

October 19, 2021

I have a hypothesis that maybe the asteroid belt between Mars and Jupiter used to be a planet that blew up. Maybe proto-humans lived there and for them Mars and Earth was what Mars is for us now – a potential escape place? They could have spaceship/spaceships orbiting the Earth around the equator until they run out of fuel/energy.

I read that some researches claim that it’s impossible, because the total mass of the belt is too little to form a planet. I find it quite ridiculous as I assume that if planet has exploded it could lose majority of it’s mass by: