The PST of stray light includes the influence of system assemble error, and reflects the real capacity of stray light suppression.

光学系统杂光指标PST的测量，包含了系统各种安装误差的影响，体现了系统杂光抑制的真实水平。

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The suppression of that light makes it easier for astronomers to then uncover the images of the planets.

FORBES: Astronomers Conduct 'Reconnaissance' Of Another Solar System