The NASA Double Asteroid Redirection Test (DART) has demonstrated the capability of successfully conducting kinetic impact-based asteroid deflection missions. The changes in the Didymos–Dimorphos mutual orbit as a result of the DART impact have already been measured. To fully assess the heliocentric outcome of deflection missions, the heliocentric momentum enhancement parameter, β _⊙, needs to be determined and disentangled from other nongravitational phenomena such as the Yarkovsky effect. Here we explore the measurability of β _⊙ resulting from DART, which we estimate simultaneously with nongravitational accelerations using a least-squares filter. Results show that successful stellar occultation measurements of the Didymos system in the second half of 2024 in addition to the ones in the 2022–2023 campaigns can achieve a statistically significant estimate of β _⊙, with an uncertainty slightly above 20% for an assumed β _⊙ = 3. Adding additional occultation measurements and pseudorange measurements from the Hera spacecraft operations at Didymos starting in 2027 decreases this relative uncertainty to under 6%. We find that pre-impact occultation observations combined with post-impact occultations would have yielded substantially higher signal-to-noise ratios on the heliocentric deflection. Additionally, pre-impact occultations would also have enabled a statistically significant β _⊙ estimate using only one additional occultation in 2023 September. Therefore, we conclude that future asteroid deflection missions would greatly benefit from both pre- and post-deflection occultation measurements to help assess the resulting orbital changes.

中文翻译：

---

动能撞击日心动量增强的可测量性：双小行星重定向测试 (DART) 任务

美国宇航局双小行星重定向测试（DART）已经证明了成功执行基于动能撞击的小行星偏转任务的能力。由于 DART 撞击而导致的 Didymos-Dimorphos 相互轨道的变化已经被测量到。为了全面评估偏转任务的日心结果，日心动量增强参数，β _⊙，需要确定并与其他非引力现象（例如雅可夫斯基效应）分开。在这里，我们探讨了可测量性β _⊙由 DART 得出，我们使用最小二乘滤波器同时估计非重力加速度。结果表明，除了 2022-2023 年活动中的观测之外，2024 年下半年对 Didymos 系统成功进行的恒星掩星测量可以实现统计上显着的估计β _⊙，假设的不确定性略高于 20%β _⊙ = 3。从 2027 年开始，在 Didymos 运行的 Hera 航天器中添加额外的掩星测量和伪距测量，将这种相对不确定性降低到 6% 以下。我们发现，撞击前掩星观测与撞击后掩星相结合，会在日心偏转上产生更高的信噪比。此外，撞击前的掩星也使得统计上显着的β _⊙估计仅使用 2023 年 9 月的一次额外掩星。因此，我们得出的结论是，未来的小行星偏转任务将极大地受益于偏转前和偏转后掩星测量，以帮助评估由此产生的轨道变化。