Reconstructing the Chelyabinsk meteor’s path with high-school math
ogleearth.com
ogleearth.com
How could they? Gravity acts on all objects not fastened to something, and one can get a very good estimate of an object's path in three dimensions if one can compute a velocity profile. Most paths in a gravitational field are curved (the exception is a path aligned with the field).
As to velocity, anything that convert kinetic energy into another kind of energy -- light, heat, noise -- causes a reduction in velocity.
The two factors above (the effect of gravity and a velocity profile) can be used to produce a very good three-dimensional path through the atmosphere, through many kinds of velocity changes, all the way to the ground.
The Russian meteor very clearly underwent a great reduction in velocity when it glowed brighter than the sun, simply because that glow represents energy, and the energy's source was the meteor's mass and velocity, which therefore had to decline. Remember that energy cannot be created or destroyed, only changed in form. Knowing the amount of energy dissipated by the bright phase, and knowing the meteor's initial mass and velocity, one can write a very good model of the object's evolution from space rock to meteorite (meaning a former meteor on the ground) and its path.