The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80–300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together $60+$ programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.

默奇森宽场阵列（MWA）是一种开放式望远镜，致力于研究低频（80-300 MHz）的南部天空。自2013年中开始运营以来，MWA在南半球打开了一个新的观测窗口，为许多科学领域提供了支持。原始设计的驱动科学目标是观察电离纪元（EoR）发出的21 cm辐射，探索射电时域，进行银河系和银河系外测量以及监视太阳，日球和电离层现象。总之 $ 60+ $ 迄今为止，程序记录了2万小时，产生146篇论文。2016年，望远镜进行了重大升级，从而实现了紧凑和扩展配置的交替。自原始阵列投入使用以来，还进行了其他升级，包括数字后端和快速响应触发系统。在本文中，我们回顾了MWA先前运行的主要结果，然后讨论了功能改进带来的新科学途径。我们将这些科学机会按照四个原始科学主题进行分组，但也包括这些类别以外的方向构想。