Will asteroids coming straight at earth appear to move, or will they appear to be stationary, with only their size increasing ?
Great question czaner! If the asteroid was moving directly towards us then we would certainly not see it move *as much*, however, in reality, it would never be moving in such a way that we wouldn't see it moving *at all*. After all the Earth is spinning and moving through space, and the asteroid is also doing so independently. For us to see no movement at all it would have to be tracking a specific spot on the surface of the Earth and heading directly to that place, moving in time with the Earth's rotation and movement around the Sun. Thankfully asteroids can't do that! But those that we see moving very little across the sky are either extremely far away (in which case they would be very faint), or moving towards the Earth as you suggested. We will still see some sideways movement over time, but it's these asteroids which we need to be wary of and track to gain a complete understanding of their orbits, ensuring they don't hit the Earth, which can lead to devastating consequences. You can read more about asteroids and their impacts under the Near Earth Objects pages in the LEARN section!