The time of the day when the sun is just below the horizon, especially the period between sunset and dark.

曙光，暮色清晨或黄昏期间当太阳处于地平线以下时，太阳光被地球的大气所折射而弥漫在天空中的光。

youdao

In the morning, when the sun is just starting to light the day, I am awakened and my first thoughts are of you.

清晨，当初升的太阳开始照亮新的一天，我从梦中醒来，首先想到的是你。

youdao

In the morning when the sun is just starting to light the day, I am awakened, and my first thoughts are of you.

当一天中黎明的第一缕阳光开始照射时，我被唤醒，并且我首先想到的是你。

youdao

When the sun is just right, rainbows of color dance in the air.

VOA: special.2009.05.25

The way he described is when you try to get down a quantum dimensions and you are standing there with your camera, just remember the sun is at your back and your shadow is always in the picture.

这种方法被他描述为,当你试着处理一个量子尺寸时,并且你试着拿着你的相机在那，记住太阳在你的背后,而你的影子总是在照片上。

麻省理工公开课 - 固态化学导论课程节选

And some designs provide power round the clock, not just when the sun is shining, by storing energy in the form of molten salt.

ECONOMIST: A new type of power plant harnesses the sun��and taxpayers

To use that excess electricity (obviously, only excess when the wind is blowing just right, or the Sun shining) to electrolyse water by passing it through a fuel cell and then store the resultant hydrogen.

FORBES: Apple Wrongfoots Greenpeace over Renewable Power for the iCloud

Who does that, who pours people drinks at eleven in the morning when everyone is just sitting there baking in the sun?

NEWYORKER: Brother on Sunday