The Earth-Sun Lagrangian point 4 is a meta-stable location at 1 AU from the Sun, 60° ahead of Earth's orbit. It has an uninterrupted view of the solar photosphere centered on W60, the Earth's nominal magnetic field connection to the Sun. Such a mission on its own would serve as a solar remote sensing observatory that would oversee the entire solar radiation hemisphere with significant relevance for protecting Moon and Mars explorers from radiation exposure. In combination with appropriately planned observatories at L1 and L5, the three spacecraft would provide 300° longitude coverage of photospheric magnetic field structure, and allow continuous viewing of both solar poles, with >3.6° elevation. Ideally, the L4 and L5 missions would orbit the Sun with a 7.2° inclination out of the heliographic equator, 14.5° out of the ecliptic plane. We discuss the impact of extending solar magnetic field observations in both longitude and latitude to improve global solar wind modeling and, with the development of local helioseismology, the potential for long-term solar activity forecasting. Such a mission would provide a unique opportunity for interplanetary and interstellar dust science. It would significantly add to reliability of operational observations on fast coronal mass ejections directed at Earth and for human Mars explorers on their round-trip journey. The L4 mission concept is technically feasible, and is scientifically compelling.

中文翻译：

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多用途太阳物理学 L4 任务

地球-太阳拉格朗日点 4 是一个亚稳定位置，距离太阳 1 天文单位，在地球轨道前方 60°。它可以不间断地看到以 W60 为中心的太阳光球层，W60 是地球与太阳的名义磁场连接。这样的任务本身将作为一个太阳能遥感天文台，将监督整个太阳辐射半球，这对于保护月球和火星探险者免受辐射暴露具有重要意义。结合适当规划的 L1 和 L5 天文台，这三个航天器将提供 300° 经度的光球磁场结构覆盖，并允许连续观察两个太阳极，仰角 >3.6°。理想情况下，L4 和 L5 任务将在太阳赤道外倾斜 7.2°，黄道平面外倾斜 14.5° 绕太阳运行。我们讨论了在经度和纬度扩展太阳磁场观测以改进全球太阳风建模的影响，以及随着当地日震学的发展，长期太阳活动预测的潜力。这样的任务将为行星际和星际尘埃科学提供独特的机会。它将显着增加针对地球的快速日冕物质抛射以及人类火星探险者在往返旅程中的操作观测的可靠性。L4 任务概念在技术上是可行的，在科学上是令人信服的。这样的任务将为行星际和星际尘埃科学提供独特的机会。它将显着增加针对地球的快速日冕物质抛射以及人类火星探险者在往返旅程中的操作观测的可靠性。L4 任务概念在技术上是可行的，并且在科学上是令人信服的。这样的任务将为行星际和星际尘埃科学提供独特的机会。它将显着增加针对地球的快速日冕物质抛射以及人类火星探险者在往返旅程中的操作观测的可靠性。L4 任务概念在技术上是可行的，在科学上是令人信服的。