标题： Rheasilvia的次级撞击可能是灶神星赤道凹槽的起源 显示英文标题

标题： Secondary cratering from Rheasilvia as the possible origin of Vesta's equatorial troughs

摘要： 小行星4谷神星有一组与赤道对齐的平行凹槽。 尽管之前的评估表明它是冲击破裂构造起源，但我们提出，赤道凹槽可能是由最大的撞击盆地雷亚希尔维亚产生的次级撞击形成的。 我们通过考虑谷神星的快速自转计算了来自雷亚希尔维亚的溅射粒子轨迹。 结果表明，次级陨石坑应与纬度平行。 特别是，如果我们假设溅射粒子以大约350-380米/秒的初始发射速度和25度的发射角度发射，那么平行赤道凹槽——迪瓦利亚沟壑就可以通过次级撞击得到合理解释。 这个模型在诸如哈乌梅亚、萨拉西亚和查尔科洛等天体上效果良好，但在水星、月球和规则卫星上则不适用。 显示英文摘要

摘要： Asteroid 4 Vesta has a set of parallel troughs aligned with its equator. Although previous evaluations suggest that it is of shock fracturing tectonic origin, we propose that the equatorial troughs can be created by secondary cratering from the largest impact basin, Rheasilvia. We calculated the trajectories of ejecta particles from Rheasilvia by considering Vesta's rapid rotation. As a result, we found that secondary craters should be parallel to the latitude. In particular, if we assume that ejecta particles are launched at an initial launch velocity of approximately 350-380 m/s and a launch angle of 25 degree, the parallel equatorial troughs, the Divalia Fossae, can be suitably explained by secondary cratering. This model works well on objects, such as Haumea, Salacia, and Chariklo, but not on Mercury, the Moon, and regular satellites.