This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute. The Earths crust is old. Billions of years old. So old that its nearly impossible to imagine. And now scientists have discovered what may be the oldest

发表于:2018-12-24 / 阅读(62) / 评论(0) 分类 Scientific American(九)月

This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute. Theres definitely methane on Marsand there are seasonal variations of how much is being released into the thin Martian atmosphere. Which means that Mar

发表于:2019-01-08 / 阅读(53) / 评论(0) 分类 Scientific American(一)月

What does an 800-pound gorilla eat? If you said: anything it wants, youre not thinking like a scientist. A scientist would say, Let me analyze the isotopic composition of its excreta and Ill get back to you. Because a new study shows that the ratio o

发表于:2019-01-08 / 阅读(42) / 评论(0) 分类 Scientific American(十二)月

AGRICULTURE REPORT — November 12, 2002: Organic Food Labeling By Mario Ritter This is the VOA Special English Agriculture Report. Last month, Secretary of Agriculture Ann Veneman announced a program

发表于:2019-01-11 / 阅读(40) / 评论(0) 分类 农业与发展

Scientists Closer to Solving Plain of Jars Mystery A new group of human remains has been uncovered on the Plain of Jars in Laos. They are believed to date back to the Iron Age, some 2,500 years ago. The Plain of Jars is in the central Lao province of

发表于:2019-01-12 / 阅读(41) / 评论(0) 分类 2016年VOA慢速英语(三)月

Compston's machine allowed such rocks to be dated with unparalleled precision. 康普斯森的仪器能以无与伦比的精确度测定这些岩石的年代。 The prototype SHRIMP was built and machined in the Earth Science department's own worksho

发表于:2019-02-17 / 阅读(58) / 评论(0) 分类 万物简史