Why Do Stars Twinkle While Planets Do Not?

Answer 1

Stars, except for the Sun, although they may be millions of miles in diameter, are very far away. They appear as point sources even when viewed by telescopes. The planets in our solar system, much smaller than stars, are closer and can be resolved as disks with a little bit of magnification (field binoculars, for example).

Since the Earth's atmosphere is turbulent, all images viewed up through it tend to "swim." The result of this is that sometimes a single point in object space gets mapped to two or more points in image space, and also sometimes a single point in object space does not get mapped into any point in image space. When a star's single point in object space fails to map to at least one point in image space, the star seems to disappear temporarily. This does not mean the star's light is lost for that moment. It just means that it didn't get to your eye, it went somewhere else.

Since planets represent several points in object space, it is highly likely that one or more points in the planet's object space get mapped to a points in image space, and the planet's image never winks out. Each individual ray is twinkling away as badly as any star, but when all of those individual rays are viewed together, the next effect is averaged out to something considerably steadier.

The result is that stars tend to twinkle, and planets do not. Other extended objects in space, even very far ones like nebulae, do not twinkle if they are sufficiently large that they have non-zero apparent diameter when viewed from the Earth.

Dr. H

Answer 2

It's obviously a factor of source and distance and Jay's answer has a good definition of Photons.

What is really interesting is, you have two, identical answers, and yet, neither attributed a source.

In regards to the question, bear in mind the planets are reflective light just like the moon. The only change in intensity would be due to change in the source. So as long as the sun doesn't twinkle, they won't.

When stars are seen in clear atmosphere like at sea or the desert they appear brighter with less twinkle. Probably our atmosphere has the greatest affect on intensity from our position.

Answer 3

Stars, except for the Sun, although they may be millions of miles in diameter, are very far away. They appear as point sources even when viewed by telescopes. The planets in our solar system, much smaller than stars, are closer and can be resolved as disks with a little bit of magnification (field binoculars, for example).

Since the Earth's atmosphere is turbulent, all images viewed up through it tend to "swim." The result of this is that sometimes a single point in object space gets mapped to two or more points in image space, and also sometimes a single point in object space does not get mapped into any point in image space. When a star's single point in object space fails to map to at least one point in image space, the star seems to disappear temporarily. This does not mean the star's light is lost for that moment. It just means that it didn't get to your eye, it went somewhere else.

Since planets represent several points in object space, it is highly likely that one or more points in the planet's object space get mapped to a points in image space, and the planet's image never winks out. Each individual ray is twinkling away as badly as any star, but when all of those individual rays are viewed together, the next effect is averaged out to something considerably steadier.

The result is that stars tend to twinkle, and planets do not. Other extended objects in space, even very far ones like nebulae, do not twinkle if they are sufficiently large that they have non-zero apparent diameter when viewed from the Earth.

Answer 4

?'s answer is good, but could use a bit more clarity. Apparently, the "bottom line" is that atmospheric turbulence tends to interfere with our perception of light sources. And, when this happens, some of the photons will either be perceived incorrectly or not at all. Now this is not so much of a problem with a a relatively large (or apparently large, because much closer) object, like a planet in our solar system. So, e.g., you probably will not notice a "twinkling" of the planet Jupiter, but will with a star like Sirius.

Answer 5

The light from a star has traveled so cfar it appears as a point, atmospheric dust and disturbances is enought to cause the light to appear to twinkle. Most of the planets are very close to earth and many of them can be seen as a disc.

Answer 6

Light is carried in small packets called photons. With bright lights, your eye is hit by huge numbers of photons all at once. If you deflect or block out a few photons, you hardly notice any difference at all. However, weird things start happening as you move the light source farther away.

Intuitively, it makes sense that things get dimmer. This is because fewer photons are hitting your eye (the photons have to spread out over a larger area). There comes a point, though where your eye is only hit by one photon at a time. At this point, if that one photon is deflected or blocked, you are unable to see any more light.

This point happens only after immense distances. It does not happen with objects in our solar system--they are two close. Even with objects like asteroids and the moons of Jupiter, barely visible to the naked eye, your eye still sees huge numbers of very dim photons at once, so there is no twinkling.

However, with stars, you see only one very bright photon at a time, and any stray air currents will make the light miss your eye momentarily. This is why stars twinkle, and the definitive proof is that astronauts have reported that in space or on the moon, with no atmosphere, the stars do NOT twinkle.

Answer 7

Planets twinkle, too, only no longer as plenty because of the fact they're plenty closer and brighter. The twinkling is led to by using the air interior the Earth's atmosphere. distinctive stars are seen in distinctive seasons because of the fact the Earth rotates around the solar, and is dealing with distinctive factors of the sky at distinctive situations. the celebrities seem to bypass around the sky each night because of the fact the Earth spins. that is an identical reason as why the solar rises and gadgets.

Answer 8

Stars are actually "suns"... that is, they are burning balls of gasses, giving off their own light,, Like all fires, they burn hotter or colder, which causes them to flicker (twinkle). Planets merely reflect the light of a glowing sun. therefore , like our moon, they emit a steady glow that does not "twinkle"

Answer 9

planets reflect and stars produce their own light. some of the twinkle is produced by solar flares and hotter tempuratures in different places of the star.