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I saw a shooting star as I was standing on the roof of my home. My home is double storey. And the height of that shooting star that I saw was maybe 10 to 13 meters. It was burned down at that height. My question is why haven't the shooting stars burnt completely when they enter the earth's atmosphere where the air is thick? Why sometimes a small piece gets to come very close to the ground and then burns?

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    $\begingroup$ Either what you saw was not a shooting star, it was a something else glowing. Or you were not able to correctly judge the height of the meteor, since you have no way of judging distance of things in the sky. Shooting stars burn up between 80000m and 120000m, they never start glowing at 10m-13m $\endgroup$ – James K Nov 23 '18 at 18:28
  • $\begingroup$ I was on second floor of my house. And it was so close. There can be no other cause or nothing else glowing because there was no transmission lines or something like that. It was so small when it burned down. It surely was a small piece of star. Maybe I misjudged the height but it sure was too close. $\endgroup$ – Aqib Ch Nov 23 '18 at 18:35
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    $\begingroup$ There are two close votes, but I'm voting to leave this question open. There's a tendency on this site to close questions that are clear and on-topic but simply not useful for our astronomy library. But meteors are on-topic, and the question is clear but misinformed. The correct response is not to close, but to downvote. JamesK has already given the most helpful advice the OP is likely to get. And after a month, the SE system automatically deletes any question with negative votes and no answers. $\endgroup$ – Reinstate Monica Nov 24 '18 at 3:42
  • $\begingroup$ To convince yourself: did you ear noise? Obviously not. $\endgroup$ – Alchimista Nov 24 '18 at 9:28
  • $\begingroup$ I agree with the Chappo's diagnosis, but not with their treatment. The question is clear but misinformed, as such it is clearly not an astronomical observation and so is off topic. I vtc as unclear. The OP has done nothing "wrong" so their question should not be downvoted. The system will delete closed questions after a certain period, but if the question is left open, it is likely to attract answers. For questions like this, the proper course of action is "close, and comment". $\endgroup$ – James K Nov 25 '18 at 21:28
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What you described is simply impossible. Meteors glow because its surface is being vaporized. When they enter the upper layers of the Earth's atmosphere they are typically travelling several kilometers per second (that's thousands of mph). They are going so fast that the air in front of it doesn't have time to get out of the way of the hypersonic meteor, so the air gets compressed. Compressed air naturally heats up, and because the air can't get out of the way, it stays very hot. This heat will vaporize the leading surface of the meteor (the "front", so to speak), making it glow very brightly. It also leaves a trail of plasma, which is the streak you see behind it.

As the meteor travels lower and lower into the atmosphere, it will slow down. Once it gets to about 15 km (9 miles up), the meteor will have slowed down to below 2 km/s (4000 mph). This speed is too slow to vaporize the surface. Thus, the meteor stops glowing red hot, and is essentially invisible from then on. Eventually it will slow down to about 150 m/s (300 mph). That's only a bit faster than terminal velocity of the average human, and slower than a jet plane. Eventually it will hit the ground at roughly the same as ambient temperature (this vaporization process is very heat efficient).

You claimed that you saw the meteor 10-13 m above your head, but this would not be possible. In order to be glowing, it would need to be travelling at least 2 km/s (4000 mph), which is not possible for a meteor as it would have already slowed down in its flight.

I think you may have been mistaken. Distance is generally hard to measure. In fact, the ancients did not know if the Sun was close by and fairly small, or far away and fairly large. The same went for the Moon. It was only until the Greeks figured out how to measure the distance using some neat trigonometry that we got the Moon's size distance and size. They also got the Sun's size and distance but it was pretty far off, though the way of measuring was correct.

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protected by James K Oct 13 at 15:21

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