最深拍摄的Gemini流星体及其小但非可忽略的终端质量
Deepest ever photographed Geminid with small but not negligible terminal mass
AI总结：
研究发现，该Gemini流星体在大气层中穿透深度达32.5公里，且大部分初始质量未能幸存，其终端高度限制保持在约38公里，为首次观测到如此深穿透的Gemini流星体。
摘要：
我们报告了2012年12月13日欧洲陨石网络（EN）在捷克部分观测到的极不寻常的Gemini火球。其独特之处在于其在大气层中的穿透深度记录（32.5公里）以及大部分初始质量在大气中剧烈减速后未能幸存。与欧洲陨石网络观测的大量Gemini流星体以及美国草原陨石网络和加拿大MORP网络观测的最亮Gemini流星体相比，发现对于初始质量大于约10克的Gemini流星体，终端高度限制不再随质量减小而降低，保持在约38公里。在此比较中，唯一例外就是本文呈现的Gemini流星体，其穿透深度几乎深6公里，终端速度极低。该流星体在大气飞行中从原始速度35.75 km/s降至6.8 km/s。初始质量仅为0.25 kg的该小流星体可能是有史以来观测到的最快陨石坠落候选体。该属于流星雨的固态流星体经历了约2 MPa的显著动态压力，因此属于造成观测到陨石坠落的小行星起源的星际体。尽管有类似Gemini事件在文献中曾被提及，但本文证明该主张存在缺陷。
英文摘要：
We report an instrumental observation of the very exceptional Geminid fireball which was observed in scope of the Czech part of the European Fireball Network (EN) on 13 December 2012 at 4h12m59.4s UT. The uniqueness of this Geminid fireball consists of the record depth of its penetration in the atmosphere (to the height of 32.5 km) and in the fact that most likely a very small fraction of its initial mass survived severe deceleration in the atmosphere and landed on the ground. Such deeply penetrating Geminid with so precise and reliable data has not yet been observed. From a comparison with a large number of Geminids observed by the European Fireball Network and all brightest Geminids from the Prairie Fireball Network in USA and the Canadian MORP Network, we have shown that for Geminids with an entry mass greater than approximately 10 grams, the terminal altitude limit does not decrease further as it does for smaller Geminids, but remains constant at around 38 km. In this comparison, we have shown that there is only one exception, and that is the Geminid presented here. This one penetrated nearly 6 km deeper with very low terminal speed for Geminids. During the atmospheric flight this Geminid meteoroid slowed down from its original speed of 35.75 km/s to 6.8 km/s. This small meteoroid with initial mass of only 0.25 kg is probably the fastest candidate for a meteorite dropping event ever observed. This solid meteoroid belonging to the meteor shower survived a significant dynamic pressure of almost 2 MPa and thus ranks among the interplanetary bodies of asteroidal origin that caused the observed meteorite fall. Although a similar Geminid event has been previously presented in the literature, we demonstrate here that this claim was flawed.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
