28 August 2022
科學家正在調查第二顆小行星與第一顆被認為殺死幾乎所有恐龍的行星相同時間撞擊地球的可能性。
該調查與最近在海洋口發現的火山口相關。
研究者認為火山口可能是由大行星創造。
科學家一直認為在6600百萬年前在墨西哥
Yucatán半島附近大行星撞擊了地球。他們認為衝擊強度相當於100億個核彈。
衝擊結果產生廣泛山火，地震和海嘯。科學家也相信產生大量化學物質到大氣導致極寒天氣。
氣候變化導致70%以上的動植物消失。所有不像鳥的恐龍死了。
那次撞擊的火山口是寬180千米深900米的大火山口。
研究人員說最新在北大西洋發現的火山口是很小的火山口。它寬約8。5千米。它被埋藏在西非幾內亞海岸400米以下的海底。
科學家發現這個火山口是用地震儀發現的。這種儀器設計是測地震和地表的其它震動訊號。
火山口由蘇格蘭（
Uisdean Nicholson， a geologist at Heriot-Watt University in Edinburgh， Scotland）的Heriot-Watt大學的地理學家發現。
Scientists are investigating the possibility that a second
asteroid
hit Earth about the same time as the one believed to have killed off nearly all dinosaur life。
The investigation is linked to a smaller crater recently discovered in the ocean。 Researchers say the crater may have been created by a large asteroid。
Scientists have long believed that a large asteroid hit Earth about 66 million years ago near Mexico‘s Yucatán Peninsula。 They estimate the force of the crash to be equal to the strength of about 10 billion nuclear bombs。
The strike， or impact， is believed to have caused widespread wildfires， earthquakes and huge ocean waves， or tsunamis。 Scientists also believe the event caused a release of chemicals into the atmosphere that led to severe cooling。
The climate-changing event is blamed for causing the disappearance of more than 70 percent of plant and animal life。 All dinosaurs that were not bird-like died out。
That strike created a huge crater about 180 kilometers wide and 900 meters deep。
Researchers say the newly discovered crater， found in the North Atlantic Ocean， is much smaller。 It is about 8。5 kilometers wide。 It is buried up to 400 meters below the seabed off the coast of Guinea， in West Africa。
Scientists found the crater by using seismic instruments。 Such tools are designed to measure earthquakes and pick up other
vibration
signals on Earth。
The crater was discovered by Uisdean Nicholson， a geologist at Heriot-Watt University in Edinburgh， Scotland。 At the time， Nicholson was working on an ocean-mapping project involving seabed spreading。 This kind of spreading is what caused the African and American continents to separate over time， leading to formation of the Atlantic Ocean。