• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>Hypervelocity Impact Symposium >Momentum transfer in hypervelocity cratering of meteorites and meteorite analogs: Implications for asteroid deflection
【24h】

Momentum transfer in hypervelocity cratering of meteorites and meteorite analogs: Implications for asteroid deflection

机译：陨石和陨石模拟的超高速衰退动量转移：对小行星偏转的影响

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Asteroid porosity ranges from 0 to >50%, with most >20%, and some asteroids exhibit a water feature in their reflection spectra. Porosity and hydration are expected to influence the momentum transferred in hypervelocity collisions. We conducted a series of measurements of the post-impact momentum, characterized by a factor ss, the ratio of the total linear momentum acquired by the target to the momentum of the impactor. We measured ss for anhydrous meteorites, samples of their asteroidal parent bodies, spanning a wide range of porosities: 7 samples of the CV3 carbonaceous chondrite Northwest Africa (NWA) 4502 (2.1% porosity), 7 samples of the ordinary chondrite NWA 869 (6.4% porosity), and 4 samples of the ordinary chondrite Saratov (15.6% porosity), as well as 2 samples of terrestrial pumice (80% porosity). We also measured hydrous meteorite analog targets, including 2 samples of terrestrial serpentine (17.9% porosity) and 4 samples of terrestrial montmorillonite (51.5% porosity), the two clay minerals that dominate the composition of the hydrous CI carbonaceous chondrite meteorites, as well as 4 samples of hydrous meteorite analog material prepared by powdering and hydrating an anhydrous carbonaceous chondrite. We found that for both anhydrous and hydrous samples ss decreased with increasing porosity, consistent with hydrocode modeling. The ss for each target type was >2 demonstrating that crater ejecta makes a significant contribution to recoil in hypervelocity collisions.. The ss values we measured for the anhydrous samples are larger, with ss = 3.55 for NWA 4502, 2.69 for NWA 869, 2.10 for Saratov, and 2.15 for pumice, than results from hydrocode modeling for 10 km/s impacts into relatively strong, porous rock targets. The momentum enhancement by ejecta (ss-1) for the moderate porosity (17.9%) hydrous serpentine targets (ss = 4.70), the highly porous (51.55% porosity) hydrous montmorillonite targets (ss = 2.79), and the intermediate porosity (-26%) CI-analogs (ss = 2.99) are much larger than ss value for anhydrous targets of similar porosity, indicating jetting of water vapor could significantly affect deflection of hydrous asteroids and comets in natural or human-induced collisions.
机译：小行星孔隙率的范围为0至> 50％，与大多数> 20％，和一些小行星在其反射光谱表现出的水的功能。孔隙度和保湿，预计影响在超高速碰撞转移的势头。我们进行了一系列的后冲击势头的测量，其特征在于，一个因子β，由目标到冲击的动量所获取的总线动量的比率。我们测量SS无水陨石，它们的小行星上级机构的样本，涵盖了各种孔隙度：在CV3的碳质球粒陨石非洲西北部（NWA）4502（2.1％的孔隙度），普通球粒陨石的7个样品的7个样品NWA 869（6.4 ％的孔隙率），和4个样品的普通球粒陨石萨拉托夫（15.6％的孔隙率）的，以及2个样本地面浮石（80％的孔隙率）的。我们还测量含水陨石模拟目标，包括陆生蛇纹石（17.9％的孔隙率）的2个样品和地面蒙脱石（51.5％的孔隙率）的4个样品中，两个粘土矿物，所述含水CI碳质球粒陨石主宰组合物，以及含水陨石模拟材料的4个样品的制备通过粉化和水合的无水碳质球粒陨石。我们发现，无论对于无水和含水采样SS随孔隙度下降，与水码模型是一致的。对于每个目标类型SS是> 2表明火山口喷出物使得在超高速碰撞反冲显著贡献..我们为无水样品中测量的SS值是较大的，具有SS = 3.55 NWA 4502，2.69 NWA 869，2.10为萨拉托夫和2.15浮石，比水码模拟结果10公里/秒的影响纳入比较强，多孔岩石的目标。动量增强由喷出物（β-1）的中等孔隙率（17.9％）的水合蛇形目标（SS = 4.70）时，高度多孔的（51.55％的孔隙率）的含水蒙脱石目标（SS = 2.79），中间孔隙率（ - 26％）CI-类似物（SS = 2.99）比用于类似孔隙率的无水目标SS值大得多，表明水蒸汽的喷射能显著影响含水小行星和彗星的偏转在自然或人为的碰撞。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号