（486958）Arrokoth的太阳星云，库珀带的原始触点二进制

论文标题

（486958）Arrokoth的太阳星云，库珀带的原始触点二进制

The solar nebula origin of (486958) Arrokoth, a primordial contact binary in the Kuiper belt

论文作者

McKinnon, W. B., Richardson, D. C., Marohnic, J. C., Keane, J. T., Grundy, W. M., Hamilton, D. P., Nesvorny, D., Umurhan, O. M., Lauer, T. R., Singer, K. N., Stern, S. A., Weaver, H. A., Spencer, J. R., Buie, M. W., Moore, J. M., Kavelaars, J. J., Lisse, C. M., Mao, X., Parker, A. H., Porter, S. B., Showalter, M. R., Olkin, C. B., Cruikshank, D. P., Elliott, H. A., Gladstone, G. R., Parker, J. W., Verbiscer, A. J., Young, L. A., Team, the New Horizons Science

论文摘要

New Horizons航天器与冷古典Kuiper Belt对象（486958）Arrokoth（以前是2014 MU69）的相遇显示了一个接触二进制的行星。我们研究了它是如何形成的，发现它是早期太阳系中温和，低速合并的产物。它的两个凸耳裂片表明，在重力崩溃的固体颗粒云中，许多较小的行星占据了低速积累。裂片的几何比对表明叶是一种共绕的二进制，它经历了角动量损失和随后的合并，这可能是由于动力学摩擦和云中的碰撞或随后的气体阻力所致。 ARROKOTH的接触二元形状由冷古典Kuiper带的良性动力学和碰撞环境保存，因此可以告知在早期太阳系中运行的吸积过程。

The New Horizons spacecraft's encounter with the cold classical Kuiper belt object (486958) Arrokoth (formerly 2014 MU69) revealed a contact-binary planetesimal. We investigate how it formed, finding it is the product of a gentle, low-speed merger in the early Solar System. Its two lenticular lobes suggest low-velocity accumulation of numerous smaller planetesimals within a gravitationally collapsing, solid particle cloud. The geometric alignment of the lobes indicates the lobes were a co-orbiting binary that experienced angular momentum loss and subsequent merger, possibly due to dynamical friction and collisions within the cloud or later gas drag. Arrokoth's contact-binary shape was preserved by the benign dynamical and collisional environment of the cold classical Kuiper belt, and so informs the accretion processes that operated in the early Solar System.

下载PDF全文

下载文献需遵守相关版权规定

论文标题