I just read that meteors range in size from a small pebble down to a grain of sand, and that when we see them across the night’s sky (there’s a meteor shower due tonight) they’re between 50-75 miles above us. So how the hell does something so tiny make such a large, bright streak of light when it burns up?
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It is burning super extra mega hot, which releases a lot of light. They streak through the atmosphere at many tens of thousands of miles per hour, compressing the air ahead of them so much that the air itself glows. It’s not so much the particle itself burning up as the air in front of it getting mega hot.
Because it’s moving fast enough to still have a ton of energy, and that energy is released over a very short time period.
A 1g meteor impacting at 30km/s will have 450kJ of kinetic energy, if that energy is converted to heat in less than a second, you’re going to have light intensity similar to a 450,000W incandescent light bulb. Even air will glow when you heat it enough.
The small meteor is moving extremely fast and basically acting like a bus crashing into the molecules of the atmosphere. This makes it get exceptionally hot and disintegrate before hitting the ground if it isn’t large. Even a bird’s feather could act to kill someone if moved fast enough, and friction that creates heat in the atmosphere tends to be quadratic (meaning moving 2x faster means 4x the resistance) in spherical objects. Energy is ~ mass * velocity^2, so even a very light object moving very fast can have a considerable amount of kinetic energy. Meteors tend to be moving in the range of 10 _kilometers_ a second. This is of the order of the fastest ballistic missiles, and those are made to be very aerodynamic.
All the previous replies answer the question “Where does this energy come from”.
Which is great and thanks for this.
I think what the OP is really asking is “How wide are some asteroid trails”.
I assume we see a super heated and glowing cylinder of air that takes an observable amount of time to cool, to stop glowing etc…
Please, does anyone have data on various trail widths and a description of what defines said widths, while the trail is glowing ?
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