Is it possible for a baseball to have as large a momentum as a much more massive bowling ball

Yes it is possible. Momentum is calculated by the mass of the object times its velocity.
For example, say a bowling ball weighs 3.0kg and is travelling at a speed of 3.0m/s. Its momentum would be 3.0×3.0=9.0 kg·m/s.
Now say we have a baseball weighing 0.20kg and it is travelling at a speed of 47.0m/s. Its momentum would be 0.20×47.0=9.4 kg·m/s, which is more than that of the bowling ball.

We can infer that star y is closer but other factors must be considered including the heat of the star, the mass, and the brightness of the star. even though star x seems dimmer it may just be less bright or contain less heat.