- Mars also can't support a thick enough atmosphere for humans because it doesn't have the same magnetic field as Earth does.
Earth's molten core creates a magnetic field surrounding our planet that helps to protect the atmosphere from the Sun. Harmful rays from the Sun are deflected by the magnetic field, so they don't hit the atmosphere and damage it.
It's thought that Mars once also had a molten core and a magnetic field, but lost it billions of years ago.
The molten core on earth remained molted because of the early impact with a mars like planet, that created the moon