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When you ask someone to draw a star, they'll probably draw something like this - or this or this.
让别人画颗星星的时候，他们可能会这样这样这样画。
Even ignoring the rainbows, this doesn't seem very scientific,
即便抛开彩虹不说，这种画法似乎非常不科学，
since we know stars are actually big hot ROUND balls of plasma and far enough away that they're basically just dots.
因为我们知道，恒星其实是又大又圆的高温等离子球，而且它们距离很远，以至于看上去基本只是些亮点而已。
So why do we draw stars that have points? The answer is surprisingly simple: we see stars as pointy.
所以为什么我们会画出带角的星星呢？答案惊人的简单：我们看到的恒星是有尖角的。
Look carefully next time you're outside on a dark night - or just look at this dot
下次在漆黑的夜晚当你在外面时，或看着这个点，
(it works best if you make the video fullscreen, close one eye, and relax the other as if you're looking at something far away).
（最好是全屏观看，睁一只眼，闭一只眼，就像看一个遥远的物体一样，这样的效果最好）。
You should see a pointy, star-like shape! In fact, it's not just humans that see pointy stars - some telescopes see them that way, too!
你应该就能看到一个带角的星星形状！其实，人类并不是唯一能看到带角星星的，很多望远镜也能看到！
This is all because light is a wave. When light from a distant source passes through an opening or around an object,
这全是因为光是一个波。当光从远处物体穿过一个缺口或绕过一个物体时，
its waves are bounced or bent slightly and interfere with each other, so the passing light picks up an imprint of that opening or object.
光线会被稍稍的反射或折射，导致互相干扰，留下缺口或物体的印记。
A straight line (whether it's a slit letting light through or a rod blocking the light) leaves its imprint
直线形状的物体（无论是一个缺口还是直直的棍子）会将光线分散开，
by spreading the light out into a perpendicular series of dashes (- like what you see when you squint!)
留下与该物体垂直的一系列短线（就像你眯着眼睛看东西一样！）
A cross creates two, perpendicular, sets of dashes, circles cause concentric rings, squares spawn a kind of dashed four-pointed star,
十字型状的物体会产生两组互相垂直的短线，圆圈产生同心环，正方形产生由短线组成的四角星，
hexagons dashed six-pointed stars; and the famous double slit experiment gives a series of dashed dashes.
六边形产生短线组成的六角星；并且著名的双缝实验产生的是一系列的短线。
My favorite diffraction pattern, though, is probably that of the Penrose tiling -
我最喜欢的衍射图案，可能是彭罗斯密铺——
it's simply gorgeous… not that you see Penrose-tiling-shaped openings very often.
非常美丽...但彭罗斯密铺形状的缺口很少见。
But… the point of all of these imprints is that they're the result of a point of light being spread out
但提到这些印记的意义在于它们都是光线
when viewed through a particular opening or past a particular object.
在通过一个缺口或绕过一个物体时被投射产生的。
For example, the Hubble space telescope has four struts that support its small secondary mirror,
例如，哈勃太空望远镜有四根柱子支撑它的副镜，
and their imprint causes the 4-pointed stars in hubble photos.
这些柱子在哈勃拍的照片上会留下四角星的印记。
And I bet you can guess the shape of the aperture on the lens that took this picture.
我打赌你能猜出拍摄这张照片的镜头的光圈形状。
Similarly, the lenses of our eyes have subtle structural imperfections called suture lines where the fibers that make up the lens meet.
我们的眼睛晶状体也相似地有一种微妙的结构缺陷——缝合线，它是构成晶状体的纤维的连接处。
These imperfections leave a very particular imprint on light as it passes by,
这些缺陷在光穿过时留下一个特别的印记，
as researchers have confirmed by shining lasers in people's eyes.
研究人员通过激光照射人眼证实了这一点。
So, even though stars themselves are just tiny round dots, by the time the light reaches our retina,
所以即便恒星本身是圆点形，当光线抵达我们的视网膜时，
it's been smeared out into a starlike shape.
还是会变成星星的形状。
Every single eye on earth will see a slightly different starlike smear depending on the exact nature of its suture lines -
世界上每双眼睛看到的星星形状都稍微有所不同，取决于缝合线的具体情况
even your left and right eyes will differ!
甚至你的左右眼看到的也不一样！
What's weird, though, is that any particular eye sees the same shape for every star -
但奇怪的是，任何一只眼睛看到的每颗星星都是一样的形状——
so while it is scientifically acceptable to draw stars like this, if you draw more than one in a single picture,
所以，虽然科学上来讲，画出这种形状的星星是可以接受的，但如果你画的图中星星不止一颗，
you better make sure they're all the exact same shape!
你最好保证它们的形状是一致的。
On top of that, since diffraction spreads longer wavelength red light out more than bluer light,
另外，由于长波、偏红光线的颜射范围比偏蓝光线的要广，
the arms of these star-shapes are actually mini-rainbows with red on the outside and blue in the middle!
星星的尖角其实是微型的彩虹，红光在外，蓝光在中间！
Which, again, you can see in hubble photographs or if you look even more carefully at a single point of light.
这些你都可以在哈勃的照片里看到，或者当你仔细盯着一个光点看时。
So as crazy as it sounds, coloring in stars with rainbows is super scientifically accurate - as long as the colors go the right way.
因此，虽然听着很疯狂，但给星星添上彩虹色的角其实是非常科学的，当然你得把颜色放对位置。
