Scientists discover there wasn’t just one asteroid which killed dinosaurs –after 66 million years
科学家们发现，6600万年前，恐龙灭绝不仅仅是因为一颗小行星的碰撞
A six-mile-long asteroid, which struck Earth 66 million years ago, wiped out the dinosaurs and more than half of all life on Earth. The impact left a 124-mile-wide crater underneath the Gulf of Mexico's Yucatan Peninsula. And, until now, it had been assumed that the asteroid acted alone.
6600万年前，一颗长6英里的小行星撞击地球，导致恐龙灭绝，地球上超过一半的生命消失。撞击在墨西哥尤卡坦半岛下方留下了一个宽124英里的陨石坑。而且，直到现在，人们一直认为小行星是“单独行动”的。
This week, scientists at Scotland's Heriot-Watt University have published new three-dimensional images of a crater made by a second asteroid that hit Earth at around the same time off the coast of West Africa.
本周，苏格兰赫瑞瓦特大学的科学家公布了第二张陨石坑的三维图像，这是第二颗小行星在大约同一时间撞击西非海岸时形成的。
The 5-mile-wide Nadir Crater was found nearly a thousand feet under the floor of the Atlantic Ocean. Dr Uisdean Nicholson was part of the group that first found it a little over five years ago, but needed seismic data from the images to confirm what had made it.
宽5英里的纳迪尔陨石坑位于大西洋海底近一千英尺处。五年前，乌斯登·尼科尔森博士是首批发现该陨石坑的研究人员之一，但需要使用图像中的地震数据来确认其成因。
"It reveals this crater in three dimensions for the first time – the first time we've ever been able to see inside an impact crater," he told The Independent on Friday. The study was published Thursday in the journal Nature Communications Earth & Environment.
周五，他接受《独立报》采访时表示：“这首次以三维方式展示了这个陨石坑——这是我们第一次能够看到撞击坑的内部。”相关研究于周四发表在《自然通讯地球与环境》期刊上。
Craters are often destroyed or deformed by erosion and can be tricky to find because they've been buried for millennia. The data provided to Nicholson's team, from the global geophysical company TGS, allowed them to see all of the crater's characteristics.
陨石坑常被侵蚀破坏或变形，且因埋藏了数千年而难以发现。全球地球物理公司TGS为尼科尔森团队提供的数据使他们能够看到陨石坑的所有特征。
"So, the crater itself is about 9,200m– that's what we call the rim. That's the main central part of the crater," Nicholson explained. "And then there's a wider set of concentric features, or circular features, around it that we call the brim. That's, I think, about 22,000m in diameter. So, that's where the sea … bed got collapsed back in."
尼科尔森解释道：“陨石坑本身大约9200米宽—— 我们称之为边缘。这是陨石坑的主要中心部分，周围还有一圈更宽的同心特征或圆形特征，我们称之为边缘。我认为其直径约为22000米。所以，那里的海床……发生了坍塌。”
The asteroid that made the crater would have been larger than 1,300 feet wide, the scientists say. The closest that humans have come to seeing an asteroid this large crashing to Earth was in 1908, when a 164-foot-wide asteroid exploded over Siberia. "We haven't had anything like this in human history," Nicholson said.
科学家表示，造成该陨石坑的小行星宽度将超过1300英尺。人类距离见证如此巨大的小行星撞击地球最近的一次是在1908年，当时一颗164英尺宽的小行星在西伯利亚上空爆炸。尼科尔森说：“人类历史上从未发生过这样的事情。”
Entering Earth's atmosphere, the asteroid would become a fireball approximately 24 to 25 times the size of the sun, generating an enormous explosion in the air that was about a thousand times larger than the 2022 volcanic eruption in Tonga.
小行星进入地球大气层后会变成一个大约24到25倍于太阳大小的火球，在空中产生巨大的爆炸，其规模比2022年汤加火山爆发还要大一千倍。
It also would have caused a 7.0 magnitude earthquake, creating a "train" of tsunamis emanating from the center of the impact. Still, compared to the Mexican "Chicxulub" asteroid, the one responsible for wiping out the dinosaurs, it's not as large in terms of the energy released.
同时，它还会引发7.0级地震，产生从撞击中心辐射开来的“一连串”海啸。然而，与导致恐龙灭绝的墨西哥“希克苏鲁伯”小行星相比，其在释放的能量方面并不算大。
Now, Nicholson hopes to test ideas about how the energy of the asteroid hit the area and what happened, as well as reconstruct the strike in more detail. The researchers want to drill down in the ocean floor to get samples of the crater to try to understand all of this and more.
现在，尼科尔森希望测试关于小行星撞击该地区的能量及其影响的想法，并更详细地重建撞击过程。研究人员希望在大洋海底进行钻探，获取陨石坑的样本，以试图了解这一切及更多信息。
Until then, having the data in 3D helps tremendously. Nicholson compared these images to newer generation medical scans. "It's like going from one old x-ray to having a full CT scan of your entire body," he said.
在此之前，拥有三维数据将大有帮助。尼科尔森将这些图像比作新一代的医疗扫描。他说：“这就像从旧式的X光片发展到全身的CT扫描一样。”
苏格拉底有一句名言：我知我无知。说的是，当你认识到的东西越多就越发现自己无知。苏格拉底认为，人对于客观世界的认识是有限的，且不可能完全认识客观世界，并且不应对客观世界刨根究底。神对于世界的规划自有安排，若人一意孤行地探索世界和自然的奥秘，则最终将亵渎甚至触怒神明。正因为人对神所构建的世界不可能实现完全认知，因此那些宣称自己能够认识和改造世界的人，本身便是无知的代言。尽管苏格拉底的关于“ 我知我无知”的观念的解读，在现在看来有失客观科学。但至少苏格拉底告诫人们，人的认知是有限的，现有的知识甚至可能存在错误和疏漏。因此，无论任何时代，我们都必须对自己的无知加以认识并通过不懈的开拓，去更新甚至颠覆固有的知识结构。我们在求学之路上也要报以我知我不知的心态，才能走得更远、终有所成。最后，祝愿每一位考研学子都能顺利上岸！
