The light areas are likely water ice.

发亮的部分可能是水冰。

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When you increase Amplitude, the light areas get lighter and the dark areas get darker.

当你增加振幅，发光体区域得到发光器并且暗区得到黑色。

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An image in which the light areas of the object rendered appear dark and the dark areas appear light.

底片像：一种映像，在里面物体的有光的部分显示出暗色，而阴暗的部位显示出光亮。

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This is why there are white and light colored buildings in many warm areas of the world.

VOA: special.2009.06.19

By focusing on the edges separating dark from light areas, the researchers classified their dozen cities into three types.

ECONOMIST: Urban geography

Light areas did get brighter, while darker spots were made visible.

FORBES: Magazine Article

Mongolian spots (technically named congenital dermal melanocytosis) are flat bluish-green, gray or light brown areas where cells called melanocytes have been trapped in a layer of the skin called the dermis.

CNN: What are Mongolian spots?