This Paper presents the feasibility of estimating the mass of an asteroid by tracking a number of probes ejected from a host spacecraft during a flyby. The probes are designed to fly by at a much closer distance to the asteroid than the host spacecraft, which lowers the risk of endangering the overall mission. The motion of these probes is perturbed due to the target asteroid’s mass, and by tracking the probes from the host spacecraft, the change in relative separation between the probes, which is directly proportional to the asteroid’s mass, can be measured with high precision. The probes are small reflective spheres that are tracked by an imager mounted on the spacecraft; however, the addition of radio transceivers inside the probes can greatly enhance the mass-recovery performance. A hypothetical mission to a main-belt asteroid with the physical characteristics of (101955) Bennu is used as a reference, and an extensive covariance analysis is performed to determine the recoverable mass accuracy under various conditions. The result shows that, under realistic assumptions, the mass of a Bennu-like asteroid can be recovered with a $1\sigma$ accuracy better than 20% from optical tracking. In case radio transceivers are considered, the recovered asteroid mass accuracy reduces to better than 5%.

本文介绍了通过跟踪飞越过程中从主机航天器弹出的多个探测器来估算小行星质量的可行性。这些探测器的设计目标是使其飞行距离与小行星的距离比与宿主航天器的距离小得多，从而降低了危及整个飞行任务的风险。这些探针的运动会因目标小行星的质量而受到干扰，并且通过跟踪宿主航天器发出的探针，可以高精度地测量探针之间相对间距的变化，该变化与小行星的质量成正比。探针是小型反射球，由安装在航天器上的成像仪跟踪。但是，在探头内部添加无线电收发器可以大大提高质量回收性能。以具有（101955）Bennu物理特征的主带小行星的假设飞行作为参考，并进行了广泛的协方差分析以确定在各种条件下的可恢复质量精度。结果表明，在现实的假设下，可以通过以下方法恢复Bennu状小行星的质量：$\mathrm{1个}\sigma$精度优于光学跟踪的20％。如果考虑使用无线电收发器，则恢复的小行星质量精度会降低到5％以上。