When it entered the Earth's atmosphere, the meteoroid created a bright fireball and exploded minutes later, generating the same amount of energy as a small nuclear weapon. The resulting shockwave blasted out windows, injuring almost people and causing millions of dollars in damages.
It also sent fragments hurling towards the surface that were recovered, and some were even used to fashion medals for the Sochi Winter Games. But what was also surprising was how much of the meteroid's debris was recovered after the explosion. While the meteoroid itself weighed over 9, metric tonnes 10, US tons , only about 1, metric tonnes 2, US tons of debris was ever recovered.
This meant that something happened in the upper atmosphere that caused it to lose the majority of its mass. Looking to solve this, Tabetah and Melosh began considering how high-air pressure in front of a meteor would seep into its pores and cracks, pushing the body of the meteor apart and causing it to explode. As Melosh explained in a Purdue University News press release :.
If the air can move through the passages in the meteorite, it can easily get inside and blow off pieces. To solve the mystery of where the meteoroid's mass went, Tabetah and Melosh constructed models that characterised the entry process of the Chelyabinsk meteoroid that also took into account its original mass and how it broke up upon entry. How about Ruskeor? That's not insulting to Russians, is it?
I hope not. Also, I would like to call it a rock instead of a meteor. I was never fond of the whole meteoroid - meteor - meteorite classification. Oh well. Was it a rock? Was it a stony-iron like rock or mostly iron? If we assume the rock is a sphere with a radius of 8. The volume of this rock would be the volume of a sphere. Well, this means it was not just an iron rock.
It would fall in the "stony" category. That's OK with me. In the Stratos jump, Felix jumped from a balloon , feet above the ground. This means that he was able to in a region with very little air resistance so that he could get up to very high speed. When he entered the lower atmosphere, he was actually going faster than terminal velocity for that level. So, the air was slowing him down.
At the terminal speed, the air drag force is equal to the gravitational force and the acceleration becomes zero. For Ruskeor, the rock was already going very fast when it entered the Earth's atmosphere.
There is no way the air could get it down to terminal velocity - there just wasn't enough distance for a rock this large. But this air resistance is essentially the reason that it explodes. How do we model air resistance? For ordinary speed objects like a basketball , we can use the following to determine the magnitude of the air drag force.
A is the cross-sectional area of the object and C is a coefficient that depends on the shape of the object. A sphere would have a C around 0. Even though this model most likely does not work for objects going as fast as the Ruskeor, I am going to use it anyway. At least it will give me a value as a rough estimate. What about the density of air? Mobile Newsletter chat dots. Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe.
Space Transportation Systems. Meteors burn up when they hit the Earth's atmosphere. Why doesn't the space shuttle?
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