Meteors

[eanassir]

Meteors

This is from the wikipedia:

"A meteor is the visible path of a meteoroid that has entered the Earth's atmosphere. Meteors typically occur in the mesosphere, and most range in altitude from 75 km to 100 km. Millions of meteors occur in the Earth's atmosphere every day.

Most meteoroids that cause meteors are about the size of a pebble. They become visible between about 40 and 75 miles (65 and 120 kilometers) above the Earth. They disintegrate at altitudes of 30 to 60 miles (50 to 95 kilometers)."

Meteor

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The following excellent animation illustrates some of the differnce between meteoroid --> meteor --> meteorite:

 

[lone wolf]

The same thing happens to "mountain" meteoroids as air gently seeks to warm them from a cold journey in the meteor stage - and what gets down to Earth can land and become a meteorite ... but they land wa-aa-ay too fast to be a mountain from space. Ergo, their depression and a hole in the place....

 

[eanassir]

"Meteors are of the same kind as meteorites, but they contain much of the inflammable materials like sulfur, phosphorus, sodium, potassium and magnesium. When these objects are stricken by some other objects, or touched by another substance which combines with them, those inflammable materials will burn.

Examples:
(1)When sodium and potassium come in contact with water, they will inflame due to their severe reaction with water.
(2)When magnesium and sulfur are touched by fire or an electric spark in the atmosphere, they will inflame.
(3)When phosphorus comes in contact with oxygen, it will inflame.


Therefore, meteors have at least one of these elements, so that if the meteor comes in contact with something that that element has an affinity to combine with; like water, fire or oxygen, then it will inflame and fall down to the earth, or it will be smashed and broken up in the space into very tiny pieces before will it reach the ground."

Meteors



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The question now is: Why does the meteor go right side once, and another time it goes to the left?
In other words: Why don't the meteors follow one direction?

 

[petros]

A meteor is a rock in space. A meteorite is a rock that has hit Earth.

 

[eanassir]

A meteor is a rock in space. A meteorite is a rock that has hit Earth.

True.

 

[Corduroy]

I see.

 

[Dexter Sinister]

The question now is: Why does the meteor go right side once, and another time it goes to the left?In other words: Why don't the meteors follow one direction?

They're in orbit around the sun, that's the direction they follow. They appear to come from different directions in the sky because the earth is moving too, so it'll depend on where in the earth's orbit and the meteor's orbit the paths cross.

 

[eanassir]

They're in orbit around the sun, that's the direction they follow. They appear to come from different directions in the sky because the earth is moving too, so it'll depend on where in the earth's orbit and the meteor's orbit the paths cross.

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The meteoroid comes from the space then becomes in contact with the mesosphere and it ignites to give this characteristic flashing light for a very short time.
Now the question is why do these flashing meteors follow different directions: so that we see some of them go to the right and others go to the left, some to the north and others to the south: without one direction?
I.e. when they fall towards the earth, they follow different directions: this is not related to the rotation of the earth; because then they will be like the sun or stars: they move towards the west; but infact they follow different directions!
And it can't be that such small pebbles are circling around the Sun, and that their orbits are nearer to the orbit of the earth.

 

[DurkaDurka]

The meteoroid comes from the space then becomes in contact with the mesosphere and it ignites to give this characteristic flashing light for a very short time.
Now the question is why do these flashing meteors follow different directions: so that we see some of them go to the right and others go to the left, some to the north and others to the south: without one direction?
I.e. when they fall towards the earth, they follow different directions: this is not related to the rotation of the earth; because then they will be like the sun or stars: they move towards the west; but infact they follow different directions!

So meteors have GPS you are saying?

 

[YukonJack]

eanassir, rather than posting about astronomy, stick to your area expertise, namely the merits of alcohol and the great taste of pork.

 

[Cliffy]

Didn't Ford stop making Meteors back in the sixties?

 

[Dexter Sinister]

... this is not related to the rotation of the earth; because then they will be like the sun or stars.

No, think about the geometry for a bit, draw a sketch of the earth's orbit if it helps, and the path of a debris stream around the sun whose orbit crosses earth's orbit, like the ones that cause the annual meteor showers. It will become apparent that the best time to see meteors is from after midnight to just before dawn, because that's when the dark side of the earth is facing the same direction as the earth's movement around the sun; it's plowing into the debris stream. There are tricks of perspective involved too. No doubt you've observed that parallel lines, like railway tracks or the edges of a highway, appear to come together off in the distance. Same thing happens with meteor trails, but because the distances are so much greater the apparent divergences from being parallel are greater. They may appear to go left and right of you as you watch, just as the edges of a highway do if you're standing in the middle of the road, but they're really parallel. The average distance between individual meteors in a shower is over 100 km, not the few meters a railway or road presents. Remember too that you're not seeing the meteor's actual path, you're seeing a projection of it onto a two dimensional surface.

There are several major meteor showers annually, known to be debris from comets, named for the constellations the meteor trails appear to point back to, a point called the radiant. There are also random meteors that can come from any direction. On an average night in a dark location, you can see three or four of those an hour, which might rise to seven or eight as dawn approaches. During a major shower you can sometimes see up to 70 or 80 an hour, though most of them aren't that active. There's one coming up in a few weeks, the South Delta Aquarid shower, July 27-29, with the radiant in Aquarius, which generally averages 10 to 20 per hour, and a much bigger one, the Perseid shower (radiant in Perseus, obviously), on August 12th, which varies from 30 to 70 per hour. Then there's the Orionids, October 20th, 10 to 30 per hour, the Leonids, November 16th, 10 to 20 per hour, and the Geminids, December 13th, 30 to 80 per hour. If you get a chance, go out and watch. Naked eye is best for viewing meteor showers, the field of view of binoculars and telescopes is too narrow to be useful.

 

[eanassir]

No, think about the geometry for a bit, draw a sketch of the earth's orbit if it helps, and the path of a debris stream around the sun whose orbit crosses earth's orbit, like the ones that cause the annual meteor showers.

It will become apparent that the best time to see meteors is from after midnight to just before dawn, because that's when the dark side of the earth is facing the same direction as the earth's movement around the sun; it's plowing into the debris stream.

There are tricks of perspective involved too. No doubt you've observed that parallel lines, like railway tracks or the edges of a highway, appear to come together off in the distance. Same thing happens with meteor trails, but because the distances are so much greater the apparent divergences from being parallel are greater. They may appear to go left and right of you as you watch, just as the edges of a highway do if you're standing in the middle of the road, but they're really parallel. The average distance between individual meteors in a shower is over 100 km, not the few meters a railway or road presents. Remember too that you're not seeing the meteor's actual path, you're seeing a projection of it onto a two dimensional surface.

There are several major meteor showers annually, known to be debris from comets, named for the constellations the meteor trails appear to point back to, a point called the radiant. There are also random meteors that can come from any direction. On an average night in a dark location, you can see three or four of those an hour, which might rise to seven or eight as dawn approaches. During a major shower you can sometimes see up to 70 or 80 an hour, though most of them aren't that active. There's one coming up in a few weeks, the South Delta Aquarid shower, July 27-29, with the radiant in Aquarius, which generally averages 10 to 20 per hour, and a much bigger one, the Perseid shower (radiant in Perseus, obviously), on August 12th, which varies from 30 to 70 per hour. Then there's the Orionids, October 20th, 10 to 30 per hour, the Leonids, November 16th, 10 to 20 per hour, and the Geminids, December 13th, 30 to 80 per hour. If you get a chance, go out and watch. Naked eye is best for viewing meteor showers, the field of view of binoculars and telescopes is too narrow to be useful.

If we seive your reply we find: the first paragraph is the axis of the subject.
The second paragraph speaks about the meteor shower, which is not our question.

Therefore, we confy ourselves to sieving the first paragraph:

There are many objections to this postulation:
Like about the debris stream around the sun: this is not correct: will such small pebbles circles around the sun at such long distance as the orbit of the earth? Of course to this you will not agree. But why such debris circle at such long distances; they should be captured by the gravity of the planets not the faraway Sun.

About the proper time for seeing such meteors is after midnight: not necessarily: we used to see many meteors early at night. Usually from 2 hours after sunset to midnight when we (children sleeping in summer time on the roofs of our houses) would be asleep at midnight.

And about the tricks of perspection as you said: this almost is not the required explanation, where they try to explain it this way: like the railroad or the highway

 

[lone wolf]

Astronomer predicts dramatic Draconid meteor shower for October 2011 | Space | EarthSky

They'll be a pretty good show in the Muddled East I hear....

 

[Dexter Sinister]

There are many objections to this postulation

Too bad for you, it happens to be true, your objections are based on a complete lack of evidence and comprehension. It's not a postulate, it's a fact. You asked a question I happened to know the answer to, and it seemed a legitimate question, not the usual sort of nonsense you talk about as science, so I gave you the true and correct answer, which is based on direct observational evidence and a simple understanding of basic geometry. You can find the data and a more detailed explanation with diagrams and photographs, in a book called Nightwatch by Terence Dickinson, pages 160 and 161 if you're interested. It probably isn't available in your benighted corner of the planet, but it's available from online suppliers.

You in your faith-based arrogant certainty, just deny everything you don't understand. You need to get past that if you ever want to comprehend the reality around you.

 

[eanassir]

Too bad for you, it happens to be true, your objections are based on a complete lack of evidence and comprehension. It's not a postulate, it's a fact. You asked a question I happened to know the answer to, and it seemed a legitimate question, not the usual sort of nonsense you talk about as science, so I gave you the true and correct answer, which is based on direct observational evidence and a simple understanding of basic geometry. You can find the data and a more detailed explanation with diagrams and photographs, in a book called Nightwatch by Terence Dickinson, pages 160 and 161 if you're interested. It probably isn't available in your benighted corner of the planet, but it's available from online suppliers.

You in your faith-based arrogant certainty, just deny everything you don't understand. You need to get past that if you ever want to comprehend the reality around you.

You think your answer is correct, but it is not; and you said it is written in such book so and so.
And you said it is a fact while it is not; and it is - as every other observation - liable to investigation and contemplation.
Too bad of you, as claiming the science and yet speak with such non-scientific arrogance.

 

[Dexter Sinister]

Well, why don't you DO some investigation and contemplation instead of just citing the only two books you ever read as the source of all knowledge and wisdom? You don't even know enough to know how wrong you are. If direct observation of cometary debris trails in orbit around the sun isn't enough for you, what would be?

 

[TenPenny]

We had a 1970 Meteor when I was younger.

 

[eanassir]

Well, why don't you DO some investigation and contemplation instead of just citing the only two books you ever read as the source of all knowledge and wisdom? You don't even know enough to know how wrong you are. If direct observation of cometary debris trails in orbit around the sun isn't enough for you, what would be?

Anyone praises himself, in fact he has dispraised himself -- a parable.

What two books do you mean?

I go with you: there may be the debris you say. Although I know that Moon which is so big in comparison to the sizes of meteors, and this Moon is captured by the gravity of the Earth, so that the Sun cannot pull it to itself.
The Universe and the Quran 2

While you cannot consider the possibility of other causes for the different directions of such meteors.
Therefore, not like me of course, you know a lot of things enough to know that you are right about everything.

 

[Dexter Sinister]

What two books do you mean?

The Quran and Al-Hilly's ignorant interpretation of it.

... I know that Moon which is so big in comparison to the sizes of meteors, and this Moon is captured by the gravity of the Earth, so that the Sun cannot pull it to itself.

You haven't the slightest understanding of orbital mechanics or you wouldn't say anything so silly, that's not the explanation at all. But there's no point in telling you the right one, you'd just deny it anyway because it isn't what Al-Hilly said.

Therefore, not like me of course, you know a lot of things enough to know that you are right about everything.

I've made no such claim, but I AM right about this.