科学美国人60秒 SSS 抱住大星系的大腿（在线收听）

Our galactic home, the Milky Way, is big. Mostgalaxies are far smaller. And it’s not easy being one of those little galaxies—a big galaxy’s gravity can rob their gas. And gas creates new stars, so losing gas spells the end of star-making. That's what happened to nearly all the small galaxies orbiting the Milky Way.

银河，是很大的。但大部分银河系星系都是超小的呢。而且要成为那些小星系中的一员还挺不容易——大星系的重力能够抢夺它们的气体层。而气体能够创造恒星，所以气体流失就意味着无法制造恒星。这就是所有围绕着银河系的那些小星系上面正在上演的悲剧。

But a small galaxy can still succeed. Take the example of Leo P. Discovered in 20052013, the galaxy Leo P lies some 5.3 million light-years from Earth. And it contains only about a hundred-thousandths as many stars as the Milky Way. But it’s thriving nevertheless.

但是小星系还是有机会逃脱的。比如2005年发现的这颗Leo P 。这颗星系Leo P 坐落在距离地球五百三十万光年的距离。并且它只含有银河系所含恒星数量的千分之一百。但它现在依然欣欣向荣的存在着。

So what’s Leo P's secret for success? Pretty simple: steer clear of gas-grabbing big galaxies. Leo P still has lots of gas. In fact, Leo P's gas outweighs its stars. Astronomers used the Hubble Space Telescope to study the small galaxy and published their findings recently in The Astrophysical Journal.

那么它能幸存的奥秘呢?十分简单：牢牢抱紧吸气的大星系的大腿。Leo P 现在还有不少气体。实际上，Leo P 的气体比它所含恒星还多。天文学家们利用哈勃天文望远镜研究了这些小星系并且已经将他们的研究发现发表在《天文物理杂志上》。

All that gas means that Leo P can keep making new stars. So the diminutive galaxy has a bright future, as long as it keeps obeying the number one rule of survival: don’t let any behemoths siphon off your gas.

有这些气体就意味着Leo P 能不断创造新恒星。所以这个小型星系无疑是有前途的孩纸，只要它保持遵守生存法则第一条：坚决抵抗虹吸气体的侵略行为。