In this paper, the feasibility of exploiting the Sun’s gravitational force to design the final phase (capture and orbit circularisation) to Mercury with a low propellant consumption has been investigated. The initial conditions, on the eccentricity and argument of pericentre, for the circularisation phase are obtained from a prime integral of motion, which takes place when the probe moves over a polar orbit. A numerical analysis has highlighted how these initial conditions allow, under the third-body effect, an optimal reduction of eccentricity (circularisation phase) with limited variations of the other orbit elements, without requiring orbital manoeuvres. Then, by introducing a small velocity variation, the phase of ballistic capture has been joined to the circularisation phase. The obtained results can encourage the exploitation of this phenomenon in future missions for the exploration of Mercury.

中文翻译：

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通过准推进剂任务观测水星

在本文中，研究了利用太阳引力设计最终阶段（捕获和轨道圆化）到水星且推进剂消耗量低的可行性。圆化阶段的初始条件，即偏心距和周长角，是从运动的素积分获得的，当探测器在极地轨道上移动时，就会发生这种运动。数值分析强调了这些初始条件如何允许在第三体效应下，在其他轨道元素变化有限的情况下最佳地减少偏心率（圆化阶段），而无需进行轨道机动。然后，通过引入一个小的速度变化，弹道捕获阶段已经加入到循环阶段。