# A question about sonic booms

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As you know when an object such as a concord or a rocket reaches the speed of sound it generates a sonic boom. So what about an entire hurricane that travels faster than sound? What kind of sonic boom would you get from the great dark spot or similar.

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Different atmospheres, different pressures, different results, Its 1.40 am and that's the best I can come up with right now!

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So what about an entire hurricane that travels faster than sound?

What hurricane travels faster than the speed of sound?

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Don't know of a hurricane that travels faster then sound, also a sonic boom is caused by something like a plane travelling through air faster then sound, a hurricane is not passing through air it is the air itself that is moving. Therefore it does not build up a pressure wave pushing the air out of the way. Apply relativity, if all the air is moving then a model plane caught up in the air just moves with the flow so doesn't push any thing out of the way.

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One problem with the reasoning of Ronin is that the air would be moving at more than the speed of sound with respect to the ground, so there would be sonic booms. As hurricanes are the result of pressure gradients in the air, I doubt they could push the flow to supersonic speeds with respect to their immediate surroundings. The shock wave would dissipate a lot energy very quickly.

I read somewhere that man was making sonic booms long before the advent of planes and rockets. The crack of a whip is a sonic boom.

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What hurricane travels faster than the speed of sound?

http://en.wikipedia.org/wiki/Great_Dark_Spot

Don't know of a hurricane that travels faster then sound, also a sonic boom is caused by something like a plane travelling through air faster then sound, a hurricane is not passing through air it is the air itself that is moving. Therefore it does not build up a pressure wave pushing the air out of the way. Apply relativity, if all the air is moving then a model plane caught up in the air just moves with the flow so doesn't push any thing out of the way.

Thats exactly what I thought, but what about relative to the surrounding atmosphere? Would there be sonic booms around the edge of the great dark spot? Im assuming the speed difference is greater than the speed of sound if voyager 2's measurements are accurate.

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Where does it say that it travels faster than the speed of sound?

What is the speed of sound in, say, the Jovian atmosphere?

You are making a number of assumptions in your original question:

As you know when an object such as a concord or a rocket reaches the speed of sound it generates a sonic boom.

Yes it does. In Earths atmosphere (the speed of sound is determined by the medium: source http://en.wikipedia....s_of_the_medium).

Are you assuming that because the Great Red Spot (for example) is moving at a speed that would be supersonic on Earth, that it is supersonic on Jupiter?

So what about an entire hurricane that travels faster than sound?

What is the speed of sound in the medium that the hurricane is travelling in?

What kind of sonic boom would you get from the great dark spot or similar.

Sonic booms are caused by objects travelling in air at supersonic speeds. A shock wave builds up on the leading edges as the air compresses. Why do you think that a mass of moving air would generate a compressed shock wave (does it?)?

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We have examples of supersonic gasses in some Nebula. What happens is some of the gas is accelerated to supersonic speeds by an exploding star, this gas then crashes into the surrounding gas heating up and glowing.

Thinking further about this.. speed of sound varys with pressure and temperature.. the more tightly knit or hotter the substance, the higher the speed of sound. The more disperse or cold the slower it is. I suppose what's happening to the gas during supersonic events is that it is building up pressure and heat to the point where it's local speed of sound is sufficient for it to begin to get out of the way. Hence a 'blade' or 'point' leading edge to a supersonic jet works better as it reduces the total area of high pressure air, compared to blunt noses and edges which are better for subsonic speeds.

Edited by rfdesigner

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