why don't planets twinkle? because in my opinion planets do not twinkle because they do not have their own light, but it totally different given in my text book?
Stars always twinkle because theyre so far away from Earth that, even through large telescopes, they appear only as pinpoints. And its easy for Earths atmosphere to disturb the pinpoint light of a star.
As a stars light pierces our atmosphere, each single stream of starlight is forced by the atmosphere to zig and zag this way and that. . . . and so stars appear to twinkle. On the other hand, planets dont twinkle (usually) simply because theyre closer to Earth. Youd know theyre closer if you looked through a telescope. Through telescopes, planets dont look like pinpoints. Instead, they look like tiny disks. And while the light from one edge of a planets disk might be forced to zig by Earths atmosphere, light from the opposite edge of the disk might zag in an opposite way. The zigs and zags cancel each other out . . . and thats why planets appear to shine steadily.planets dont twinkle you might see them twinkling a little if you spot them low in the sky. Thats because, in the direction of any horizon, youre looking through more atmosphere than when you look overhead. Even planets cant withstand too much atmosphere, because its the atmosphere that makes them twinkle!