月球比之前认为的要老4000万年 | 六级难度

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月球比之前认为的要老4000万年
难度：六级难度
Scientists say a mineral found in moon dust suggests Earth's moon is 40 million years older than scientists had believed.
科学家表示，在月尘中发现的一种矿物质表明，月球比科学家之前认为的要老4000万年。
The finding was made by researchers who examined moon samples gathered by astronauts from the lunar surface in 1972 – the last time humans walked on the moon.
这一结论是由研究人员对1972年宇航员从月球表面采集的月球样本进行研究后得出的，那是人类最后一次在月球上行走。
The samples were part of a collection of 110 kilograms of dust and rock returned to Earth for scientific study.
这些样本是宇航员带回地球进行科学研究的110公斤尘埃和岩石的一部分。
The American space agency NASA says the leading theory on how the moon formed involves a huge crash.
美国航空航天局表示，关于月球形成的主要理论涉及一次巨大的碰撞。
NASA says a Mars-sized object likely crashed into Earth and released material from both objects, which formed the moon.
美国航空航天局表示，一个火星大小的物体可能撞上了地球，使得这两个物体释放出物质，形成了月球。
But the exact timing of when the moon was created has been difficult to identify.
但月球形成的确切时间一直难以确定。
A new study based on the 1972 samples suggests the moon formed about 4.46 billion years ago.
一项基于1972年样本的新研究表明，月球形成于大约44.6亿年前。
The research was led by a team from the Field Museum of Natural History in Chicago, Illinois.
这项研究是由伊利诺伊州芝加哥菲尔德自然史博物馆的一个团队领导的。
The findings were recently published in a study in Geochemical Perspective Letters.
最近发表在《地球化学观点快报》杂志上的一篇研究论文陈述了这些结论。
The study examined small crystals found in the lunar dust.
这项研究检查了在月尘中发现的小晶体。
The team said the crystals contained a mineral called zircon.
研究小组表示，这些晶体中含有一种名为锆石的矿物质。
The zircon is believed to have formed when the lunar surface cooled after being in a melting state after the crash.
据信，锆石是在撞击后月球表面熔化后冷却时形成的。
The method used to estimate the age of the dust sample is called atom probe tomography.
用来估计月尘样本年龄的方法叫做原子探针断层摄影术。
This method had not been developed when the sample was collected 51 years ago, said Philipp Heck.
菲利普·赫克表示，51年前采集样本时，这种方法还没有被开发出来。
He is the lead writer of the study and the senior director of research at the Field Museum of Natural History.
他是这项研究的主要作者，也是菲尔德自然史博物馆的高级研究主任。
NASA said the lunar sample was collected from an area known as the Taurus-Littrow valley on the near side of the moon.
美国航空航天局表示，月球样本是从月球近侧的金牛-利特罗夫峡谷采集的。
The near side of the moon is the side that always faces Earth.
月球的近侧是始终面向地球的一侧。
The sample had been stored at NASA's Johnson Space Center in Houston, Texas.
样本被保存在美国航空航天局位于得克萨斯州休斯敦的约翰逊航天中心。
Heck noted that zircon is a very strong mineral that can "survive the breakdown of rocks during weathering."
赫克指出，锆石是一种非常坚固的矿物质，可以“在岩石风化过程中幸存下来”。
The new study followed an earlier one carried out in 2021.
这项新研究是在2021年进行的一项早期研究之后进行的。
In that study, researchers examined how many atoms of uranium and lead were contained in the zircon crystals.
在那项研究中，研究人员检查了锆石晶体中含有多少铀和铅原子。
They then estimated the age of the mineral based on differences in the decay of the radioactive uranium to lead over time.
然后，他们根据放射性铀随时间衰减成铅的差异来估计这种矿物质的年龄。
But the purpose of the new study was to confirm the earlier study's results, which were not considered conclusive.
但这项新研究的目的是证实早期研究的结果，早期研究结果并不被认为是确凿的。
The examinations of the sample material were carried out atom-by-atom with very sensitive instruments, the researchers said.
研究人员表示，他们用非常灵敏的仪器对样品材料逐个原子进行研究的。
Jennika Greer is a researcher in the School of Geographical and Earth Sciences at the University of Glasgow in Scotland.
詹妮卡·格里尔是苏格兰格拉斯哥大学地理与地球科学学院的研究员。
She helped lead the study.
她帮助领导了这项研究。
Greer told Reuters news agency the finding is "a great example of what the nanoscale, or even atomic scale, can tell us about big-picture questions."
格里尔告诉路透社，这一发现是“从纳米的角度，甚至原子的角度，告诉我们大问题的一个很好的例子。”
Heck, from the Field Museum, said the huge crash that formed the moon was a major event that changed Earth's rotational speed.
来自菲尔德博物馆的赫克表示，形成月球的巨大碰撞是改变地球自转速度的重大事件。
He added, "The formation date of the moon is important as only after that Earth became a habitable planet."
他补充说：“月球的形成日期很重要，因为只有在月球形成之后，地球才能成为可居住的行星。”
Greer said she hopes the team's finding can be a basis for answering many remaining questions about the moon.
格里尔说，她希望该研究小组的发现能成为回答许多关于月球的剩余问题的基础。
"It's amazing being able to have proof that the rock you're holding is the oldest bit of the Moon we've found so far."
“能够证明你手中的岩石是我们目前为止发现的最古老的月球碎片，这真是太棒了。”
She added, "When you know how old something is, you can better understand what has happened to it in its history."
她补充说，“当你知道某样东西有多古老时，你就能更好地了解它在历史上发生了什么。”
I'm Bryan Lynn.
布莱恩·林恩为您播报。