美科学家称发现太阳系第九行星

Researchers are now pretty certain there's a ninth planet in the solar system.
研究人员如今相当确定，太阳系中存在着第九颗行星。

Konstantin Batygin and Mike Brown, two CalTech scientists, say the new planet is about 10 times the mass of Earth and has an atmosphere of hydrogen and helium. Science magazine reports that the mysterious "Planet X" moves in a distant orbit beyond Neptune.
两名来自加利福尼亚理工学院的科学家康斯坦丁·巴特金和迈克·布朗，称新行星的质量大约是地球的十倍，其大气中有含有氢和氦。据《科学》杂志报道，这颗神秘的X行星的运行轨道远在海王星之外。

The researchers haven't observed Planet X itself, but believe it exists because of the unique configuration of six objects when they come closest to the sun, according to Science.
《科学》称，尽管研究人员目前尚未观测到X行星的本尊，但他们在近距离观测太阳时发现六个星体的排位很奇特，因此他们确信一定存在X行星。

The scientists say that there's a 0.007 percent probability that the configuration is due to chance, and instead are confident it's a ninth planet. They believe they will observe the planet with a telescope within five years, according to The Associated Press.
科学家称，这样奇特的排位若是纯属巧合，其几率仅为0.007%，因此他们坚信这一定是因为有第九颗行星存在的缘故。美联社称，科学家们相信五年内他们一定能用望远镜观测到这个行星。

So where did this possible planet come from? Scientists have previously speculated that there could be a missing planet in our solar system, with some theorizing that a collision caused it to be ejected out of our system some 4 billion years ago. That collision may have been with Jupiter.
那么这颗可能存在的行星到底来自哪里呢？科学家们曾根据理论研究猜测，大约四十亿年前的一场碰撞将一颗行星弹出太阳系，从此这颗行星便下落不明。碰撞的另一颗行星可能是木星。

"Although we were initially quite skeptical that this planet could exist, as we continued to investigate its orbit and what it would mean for the outer solar system, we become increasingly convinced that it is out there," Batygin said in a statement. "There is solid evidence that the solar system's planetary census is incomplete."
“虽然一开始我们对这颗行星的存在持怀疑态度，但是随着我们进一步研究其运行轨道以及其对外太阳系的影响，我们越来越确信它的存在。”巴特金在一份陈述中如是说道，“有确切证据表明，行星普查的数据并不完整。”

Batygin and Brown described their findings in The Astronomical Journal on Wednesday.
20日，巴特金和布朗在《天文学期刊》中阐述了他们的发现。

The discovery is also the second time that Brown has reshaped the way we think about the solar system. In 2005, he made a key discovery that led scientists to reclassify Pluto as a dwarf planet. In a statement on Wednesday, Brown -- whose Twitter handle is @plutokiller -- alluded to the role he played in getting Pluto declassified, noting that the new discovery was 5,000 times the mass of Pluto and was definitely a planet.
这个新发现也是布朗第二次改变我们对太阳系的看法。2005年，他的一项重要发现引导科学家们将冥王星重新归类为矮行星。布朗的推特名是冥王星杀手（@plutokiller），暗示自己在推翻冥王星地位这一事件中起主要作用；他于20日发表的一份陈述中说道，这次的新发现，其质量是冥王星的5000倍，因此它绝对是一颗行星。

"All those people who are mad that Pluto is no longer a planet can be thrilled to know that there is a real planet out there still to be found," he said.
布朗说：“冥王星的行星地位被推翻后，许多人很生气，不过现在有一颗真正的新行星正等待着去发现，这可有他们乐呵的啦。”

英文来源：赫芬顿邮报
译者：赵潇逸
审校&编辑：丹妮