流星进入大气层的速度从[11公里/秒,72公里/秒][1]。这些速度是如此之大,如果一个陨石击中表面速度,释放的能量会更足以蒸发陨石撞击,因此留下的最初影响身体。然而,在秋天,陨石减缓由于与大气摩擦。摩擦力正比于陨石半径的平方(横截面),但质量是成正比的立方体半径(体积)。这意味着更大的陨石减慢,越少越快它击中表面。过去一个给定的大小,大气中不提供足够的破坏力量。因此,所有陨石超过限制时蒸发的影响。有多大,大小限制您可以简单地看看地球上更大的陨石:[霍巴陨石][2]。[![在这里输入图像描述][3]][3](图片取自[TripAdvisor和提交的用户huys25][4])因此,什么你的照片显示不是陨石(也会有其他原因在大小这么说),也没有的。 The remains of large meteorites often reduce to small fragments that broke from the main body before impact, or [impactites][5]. Impactites are small pieces of rock that might contain meteorite materials but are not unaltered pieces of it. Said that, once a meteorite is found the calculation of the original size considers the final size, the speed and angle of impact (computed from crater geometry) and the meteorite composition among other parameters. There are many online calculators that allow you to have a rough estimate of the size of a crater that a meteorite like that would leave. For example the [Convertalot Asteroid Impact Calculator][6]. From the picture it looks like porous rock, so plugging in a density of 1.5 g/cm$^3$ and impact angle of 45°, a fairly low speed of 20 m/s, and a diameter of 20 m, it would have produced an impact crater 177 meters in diameter and 44 meters deep. Definitely a landscape feature difficult to miss. Finally, from the shape of what you show in the picture, I don't see how it can be associated to a meteorite, as it doesn't look like one at all. In that line, it could resemble the central peak of an impact crater. Like the one visible at the center of [Tycho crater][7] on the Moon. [![enter image description here][8]][8] ([Image source][9]: Wikipedia - Tycho crater on the Moon: mosaic of images, made by Lunar Reconnaissance Orbiter. Width of the image is 120 km.) However, if the central peak were that well preserved you would expect the rim of the crater to be well preserved too, and from what you say, that doesn't seem to be the case. [1]: https://www.amsmeteors.org/meteor-showers/meteor-faq/ [2]: https://en.wikipedia.org/wiki/Hoba_meteorite [3]: https://i.stack.imgur.com/dEmOb.png [4]: https://www.tripadvisor.ca/Attraction_Review-g1137965-d3609771-Reviews-Hoba_Meteorite-Grootfontein_Otjozondjupa_Region.html#photos;aggregationId=101&albumid=101&filter=7&ff=292121881 [5]: https://en.wikipedia.org/wiki/Impactite [6]: http://www.convertalot.com/asteroid_impact_calculator.html [7]: https://en.wikipedia.org/wiki/Tycho_(lunar_crater) [8]: https://i.stack.imgur.com/thYrv.png?s=300 [9]: https://en.wikipedia.org/wiki/Tycho_(lunar_crater)#/media/File:Tycho_LRO.png