Mars is further out in the solar system, and I'm assuming it was further out than Theia when the collision occurred. The article doesn't say no planets can hav

Mars is further out in the solar system, and I'm assuming it was further out than Theia when the collision occurred. The article doesn't say no planets can have water, but just that originally Earth was too close to the Sun to have liquid water. Theia, according to this hypothesis, was not.