识别星际物体撞击坑
Identifying Interstellar Object Impact Craters
摘要：
近年来，两个星际天体（ISOs）的发现引起了人们对限制其物理性质及其形成机制的极大兴趣。然而，它们在我们的太阳系中短暂的旅行只允许不完整的描述。我们调查的途径，以确定陨石坑，可能已产生的ISO影响地球太阳系机构，特别是对月球的关注。ISOs的一个显著特征是与小行星和彗星相比，它们的相遇速度相对较高。当地恒星运动学表明，地球太阳系机构应该经历了超过100公里/秒的订单统一ISO的影响。通过运行流体动力学模拟不同的质量和冲击速度的弹丸，高达100公里/秒，我们展示了如何后期等效规定，瞬态弹坑尺寸是不足以推断弹丸的速度。另一方面，固定直径的弹坑内的熔体体积可能是识别ISO弹坑的潜在途径，因为更快的撞击产生更多的熔体。该方法要求熔体体积与射弹的能量成比例，而弹坑直径与点源极限（子能量）成比例。鉴于在太阳系中最多可能只有几个ISO撞击坑，而且撞击速度至少达到100公里/秒时，瞬时撞击坑的尺寸不是一个显著特征，因此，确定ISO撞击坑是一项具有挑战性的任务。熔体体积和高压岩石学可能是诊断功能，一旦大量的材料可以在原位分析。
英文摘要：
The discoveries of two Interstellar Objects (ISOs) in recent years has generated significant interest in constraining their physical properties and the mechanisms behind their formation. However, their ephemeral passages through our Solar System permitted only incomplete characterization. We investigate avenues for identifying craters that may have been produced by ISOs impacting terrestrial Solar System bodies, with particular attention towards the Moon. A distinctive feature of ISOs is their relatively high encounter velocity compared to asteroids and comets. Local stellar kinematics indicate that terrestrial Solar System bodies should have experienced of order unity ISO impacts exceeding 100 km/s. By running hydrodynamical simulations for projectiles of different masses and impact velocities, up to 100 km/s, we show how late-stage equivalence dictates that transient crater dimensions are alone insufficient for inferring the projectile's velocity. On the other hand, the melt volume within craters of a fixed diameter may be a potential route for identifying ISO craters, as faster impacts produce more melt. This method requires that the melt volume scales with the energy of the projectile, while crater diameter scales with the point-source limit (sub-energy). Given that there are probably only a few ISO craters in the Solar System at best, and that transient crater dimensions are not a distinguishing feature for impact velocities at least up to 100 km/s, identification of an ISO crater proves a challenging task. Melt volume and high-pressure petrology may be diagnostic features once large volumes of material can be analyzed in situ.
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。
