经济学人下载:天文学:新星诞生(1)

Science and Techonology
科技

Astronomy: De Nova Stella
天文学：新星诞生

Astronomers predict a Stella explosion will happen in 5 years time.
天文学家预测5年之内会发生一次星际爆炸

Amateur astronomers have a new date for their diaries.
对于业余天文学家们来说这是一个新篇章。

In 2022, in the constellation of Cygnus, they will be treated to the sight of a nova, or “new star”.
2022年，他们将目睹天鹅座星系中出现的一颗新星，即“新见星”的场面。

By themselves, novas are not particularly noteworthy.
不过对于他们来说，新星现象并不是特别罕见。

Several dozen a year happen in Earth’s home galaxy, the Milky Way, alone. But this one will be special for two reasons.
仅就地球的母星系-银河系而言，每年都会出现数十次。但这一次的新星之所以格外引人瞩目，是因为以下两个原因。

One is its intensity: provided you are somewhere reasonably dark (in the countryside, in other words, rather than a big city) it will be bright enough to be seen by the naked eye.
第一个原因在于它的亮度：假若你在某些相当黑暗的地方（换言之，在乡村而不是大城市），那么以肉眼就能清楚地看见它；

The second is that it will be the first nova whose existence was predicted before the fact.
第二个原因在于它将是第一个被观测到之前就被预测存在的新星。

Assuming everything goes according to schedule, the credit for that will belong to Lawrence Molnar, an astronomer at Calvin College, in Michigan, and his team,
一切顺利的话，这一成绩将属于密歇根州卡尔文学院的天文学家Lawrence Molnar以及其团队，

who have set out their predictions in a paper to be published soon in the AstrophysicalJournal.
该团队预测性的文章不久后将要在天体物理学日报中发表。

It is a tale of scientific serendipity.” Nova ”,
这是科学探索过程中的一次意外惊喜。

which is Latin for “ new ”, comes from the title of a book (also the title of this article) published in 1573 by Tycho Brahe, a Danish astronomer.
“Nova”一词在拉丁语中意为“新生的”，这个词在1573年，丹麦天文学家第谷·布拉赫（Tycho Brahe）撰写的书中首次（同时也在其书名中）出现。

This recorded what would now be called a supernova that had happened the year before.
在书中，布拉赫对一颗在一年之前（1572年）爆发的“新星”（目前来看，称为超新星更加准确）进行了记述。

By proving that the “ new star ” in question was a very great distance away—at the least,
布拉赫论述证明了这颗有待商榷的“新星”其实距离地球非常遥远，

further than the Moon—Brahe dealt a mortalblow to the Aristotelian belief, widespread in Europe at the time, that the heavens were perfect and unchanging.
至少比月球与地球的距离要远得多。这一观点对当时主流的亚里士多德学派造成了毁灭性的打击，因为在16世纪的欧洲，人们普遍认为天宇是完美无缺、永恒不变的。

But the name is a misnomer. Novas are not new stars.
但是，“新星”这个名称其实并不准确。

Rather, they are explosions that take place on existing ones, drastically but temporarily increasing their brightness.
新星并不是刚刚诞生的恒星，而是原有的恒星发生爆炸，从而导致短时间内亮度急剧增加。

There are several kinds, but Dr Molnar’ s nova will be caused when one member of a two-star system collides with the other, causing an enormous and violent outpouring of energy.
新星的形成原因多种多样，而莫尔纳博士预测到的这颗则是由于双星系统中的两颗子星相互碰撞，造成巨量能量释放。