Question

why do stars appear twinkling

Answer 1

stars are gaseous in nature and Stars twinkle when we see them from the Earth's surface because we are viewing them through thick layers of turbulent (moving) air in the earths atmosphere .

Answer 2

Stars appear to be twinkling due to the weather and climate disturbances if we see from the earth.In other way, we can say that the starlight get bent from the air particles in the atmosphere from which when we see from different angles appear to be slightly brighten or more brighten.It appears like twinkling.
Hope it helps u.