unenuitblanche周围记

    发现比赛完之后,果然如李莫涵所说,我开始过得比较轻松,昨天手提电脑的主板烧掉了,但心情不怎么样坏,反而觉得有机会只拿本课本去上课,爽得不得了,老油条了一点啦...

星期三,早上两节课,7点半开始,到9点钟结束,于是到外面取钱去,发现自己很久没消费了,钱还是够用,体会到了钱的确只是一个数字的问题.我在想，什么时候把数字弄大一点呢？取钱的路上一直犹豫要不要去超市买块牛肉回来煎。。。后来作罢，有点远，就近买了四个鸡蛋。

回到宿舍，什么都脱掉，看了《古国三部曲》第二部，一章，然后到头就睡。。。一共就醒了两次，十一点一次，看了一下手机，没人找。。。一点多一次，又看了一下手机，还好。记得第一个月的时候，很多事忙，手机几乎什么时段都有人找，现在好了，它也很老油条的躺在桌面上。

今天阴天，所以起来的时候总觉得自己是不是睡过头了，死命的看手表，都看了4，5次了，半个小时之内。有种幻觉，是自己睡到世界尽头了？所有人都消失了。。。还是，我会不会迟到？神经病。。。开始煮面吃。洗衣服。本来还想拖一下地板，想了一想，算了，等有阳光的日子再说。

11 October 2008
From New Scientist Print Edition. Subscribe and get 4 free issues.

    WHY are Saturn's rings so spectacular? It could be that the planet managed to cling onto a moon when all the other gas giants in our solar system had already lost theirs. Today's rings formed when the moon was smashed up.
    为什么土星的光环如此壮观?可能是因为在我们太阳系的其他气态巨星已经失去自己的卫星的时候,土星捕获了一个月亮.今天的光环就是当时那个月亮被搅碎的时候形成的.

    Sebastien Charnoz and colleagues at the University of Diderot, Paris, suggest it was during the "late heavy bombardment", 700 million years after Saturn formed, that a chunk of debris collided with one of the planet's moons. Because the moon was orbiting at just the right distance from Saturn when it shattered - within the so-called Roche limit - the tiny pieces formed the rings instead of dispersing.
    巴黎狄德罗大学的Sébastien Charnoz等人认为 在土星形成的7亿年后," 迟到的猛烈轰击"中一大块碎片与土星的其中一个月亮相撞.因为哪一个月亮当时刚好运行到土星引力最弱的一段距离----处于所谓的"洛希极限"----撞击留下的小碎片没有消失而是形成了土星的光环.

    This could explain why other planets don't have rings like Saturn's. Even if other planets had moons within their Roche limits at the birth of the solar system, the team's calculations show that the moons would soon been dragged down into the planet or unshackled from their orbits. Yet Saturn's rapid rotation meant it could hold a satellite within its Roche limit until the bombardment. The work will appear in the journal Icarus.
    这可以解释为什么其他星球没有像土星那样的光环.即使其他星球在太阳系诞生的时候有月亮在洛希极限距离上,研究小组的运算结果显示那些月亮会很快就被引力拖到星球上面去或者是从它们的轨道中脱离出去.然而,土星的高速自转意味着它能够在洛希极限中保持着一个卫星直到"猛烈轰击".研究将会在Icarus杂志上刊登.

    Ken Rice from the Institute of Astronomy in Edinburgh, UK, says the team's way of showing Saturn's uniqueness among gas giants is interesting, but that their hypothesis cannot be proved until we have better ways of modelling the evolution of the solar system.
    英国爱丁堡天文学研究所的Ken Rice说,研究小组展示土星在气态巨星中的唯一性的方式很有趣,但是在我们能更好地模拟出太阳系进化过程之前,他们的假设不能被证实.