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How heavy is the Milky Way in comparison to its neighbor galaxy, Andromeda?
和邻居仙女座相比，我们的银河系到底有多大？
Well, depends how you calculate it.
好吧，这就要看你如何计算。
In 2006 one group of astronomers figured the Milky Way was twice as massive as Andromeda.
2006年一组天文学家指出银河系的质量是仙女座的2倍。
A 2009 estimate evened the score, calculating that the two galaxies are equal in mass.
而2009年的结论则表示二者质量持平。
Now a new formula suggests we're only half the mass of Andromeda.
现在的最新结论得出我们只有仙女座星系的一半。
To come up with that number, astronomers first measured the speed and distance of galaxies between three and 10 million light-years away.
这个数字是天文学家们首次根据3百万到一千万光年之间的星系的速度和距离所得出。
That allowed them to calculate the deformation of spacetime, and thus the mass, of our stellar neighborhood, aka the Local Group—a group of more than 50 galaxies, in which the Milky Way and Andromeda dominate.
这些数据可以计算出时空弯曲的程度，从而也可得出我们邻居，一个含有50个星系以上被称为本星系群的质量大小，我们银河系和仙女座都包含在这个星系群中。
They deduced the center of mass between the two heavyweights and found that Andromeda may indeed be twice as massive as the Milky Way.
他们根据二者的重量级推导出质心，然后发现仙女座也许真的是银河系的2倍。
The results are in the Monthly Notices of the Royal Astronomical Society.
这项研究结果已在《皇家天文协会每月通告》杂志上发表。
The researchers say this new model might be more accurate than past ones, because it accounts for dark matter far from each galaxy's center—assuming the data's right, that is.
研究人员表示这种新的模型也许比之前那些都精确，因为它是根据远离每个星系中心的暗物质计算—假设这些数据都正确，那就是正确的。
"Well, I never bet money on anything.
是的，我从来不为任何事情打赌。
Because I'm aware of all the uncertainties and approximations."
因为我会意识到所有不确定和大概的情况。
Lead author Jorge Penarrubia of the University of Edinburgh.
这项研究的首席作家爱丁堡大学的乔治佩娜拉比亚这样说道。
"One year from now, two years from now, some clever guy will come and say, ‘Hey, you forgot to include this, actually when you do everything changes,’ and then you will have to accept that."
从现在起的1年，2年，有些自以为聪明的家伙也许会出现：嘿，你忘记将这个算在内，实际上，当你已经开始，任何事情都在变。然后你就不得不接受。
For now, we'll just have to accept that we live in the wimpier of the two galaxies.
从现在开始，我们将不得不接受我们居住在这两个星系中的那个较小的一个上面。
At least until the next weigh-in.
至少，直到下一次有人比重前只能接受现在的结果。
