Institut für Geophysik und extraterrestrische Physik, Technische Universität Braunschweig, Mendelssohnstrasse 3, D-38106 Braunschweig, Germany.
Centre for Energy Research, Hungarian Academy of Sciences, H-1121 Konkoly Thege Street 29-33, Budapest, Hungary.
Science. 2015 Jul 31;349(6247):aaa5102. doi: 10.1126/science.aaa5102. Epub 2015 Apr 14.
Knowledge of the magnetization of planetary bodies constrains their origin and evolution, as well as the conditions in the solar nebular at that time. On the basis of magnetic field measurements during the descent and subsequent multiple touchdown of the Rosetta lander Philae on the comet 67P/Churyumov-Gerasimenko (67P), we show that no global magnetic field was detected within the limitations of analysis. The Rosetta Magnetometer and Plasma Monitor (ROMAP) suite of sensors measured an upper magnetic field magnitude of less than 2 nanotesla at the cometary surface at multiple locations, with the upper specific magnetic moment being <3.1 × 10(-5) ampere-square meters per kilogram for meter-size homogeneous magnetized boulders. The maximum dipole moment of 67P is 1.6 × 10(8) ampere-square meters. We conclude that on the meter scale, magnetic alignment in the preplanetary nebula is of minor importance.
行星体磁化的知识约束了它们的起源和演化，以及当时太阳星云的条件。基于罗塞塔着陆器菲莱在彗星 67P/楚留莫夫-格拉希门克（67P）上下降和随后多次着陆期间的磁场测量，我们表明在分析的限制范围内没有检测到全局磁场。罗塞塔磁强计和等离子体监测器（ROMAP）套件的传感器在彗星表面的多个位置测量到的磁场强度小于 2 纳特斯拉，对于米级大小的均匀磁化巨石，上特定磁矩<3.1×10(-5) 安培平方米每千克。67P 的最大偶极矩为 1.6×10(8) 安培平方米。我们的结论是，在米级尺度上，前星云的磁场排列的重要性较小。
