Maintaining long-term wavefront stability is critical for the Habitable Worlds Observatory (HWO), which targets contrasts approaching $10^{-10}$ and therefore requires continuous dark-zone maintenance using high-order wavefront sensing and control (HOWFSC). Prior work has advanced HOWFSC algorithms and profiled candidate implementations on radiation-hardened processors, highlighting a substantial gap between the computational demands of LUVOIR-scale HOWFSC and the capabilities of current onboard spacecraft hardware. In this paper, we argue that this gap can be closed by offloading the HOWFSC pipeline to a dedicated co-flying compute satellite at Sun-Earth L2. This approach enables the use of modern, radiation-tolerant high-performance processors without increasing risk to the primary observatory. We show that such an architecture can increase the end-to-end control cadence from the sub-hertz regime typical of radiation-hardened onboard processing or ground-in-the-loop operation to tens and even hundreds of hertz. We evaluate commercial hardware platforms in terms of performance and feasibility, and we propose custom architectures that enable higher control frequencies with significant power consumption reductions. Finally, we outline system-level considerations for co-flying compute, including reliability, satellite integration, and inter-satellite communication constraints.

翻译：维持长期波前稳定性对于"宜居世界天文台"(HWO)至关重要，该天文台旨在实现接近$10^{-10}$的对比度，因此需要通过高阶波前传感与控制(HOWFSC)技术持续维护暗区。先前的研究已推进了HOWFSC算法的发展，并在抗辐射处理器上分析了候选实施方案，结果表明LUVOIR规模的HOWFSC计算需求与当前星载硬件的处理能力之间存在巨大差距。本文论证了通过将HOWFSC处理流程卸载至日地L2点伴飞专用计算卫星，可弥合这一差距。该方案使得在不增加主观测站风险的前提下，采用现代耐辐射高性能处理器成为可能。我们证明，此类架构可将端到端控制频率从抗辐射星载处理或地面回路操作典型的亚赫兹量级，提升至数十甚至数百赫兹。我们从性能和可行性角度评估了商用硬件平台，并提出了能够以显著降低功耗实现更高控制频率的定制架构。最后，我们概述了伴飞计算系统的总体考量，包括可靠性、卫星集成以及星间通信限制。