单词：Matson system
单词：Matson system 相关文章
This is Scientific American's 60-Second Science. I'm John Matson. Got a minute? In a laboratory vault outside Paris is a small cylinder of platinumiridium alloy that serves as the standard for all mass measurements worldwide. By an 1889 international
Scientific American(一)月
This is Scientific Americans 60-SecondScience. Im John Matson, got a minute? Say you need a diamond. You could go downto the jeweler, or you could put some carbon deep underground and let it sitfor a couple billion years. Or you could hop in a starsh
Scientific American(八)月
This is Scientific American's 60-Second Science. I'm John Matson. Got a minute? Earth's surface is dominated by oceans. But where did all that water come from? Asteroids and comets smashing into the early Earth have long been thought to be a promisin
Scientific American(十)月
This is Scientific American's 60-Second Science. I'm John Matson. Got a minute? On November 8th, Russia launched a probe toward the tiny Martian moon Phobos. The launch was picture-perfect, and the spacecraft, called PhobosGrunt, soared into the nigh
Scientific American(十一)月
KELLY MCEVERS, HOST: Art lovers are in Miami Beach this week because it's Art Basel, the world-class art fair. Just a short walk away, there's also Design Miami, which begins today. As NPR's Mandalit del Barco reports, Design Miami has become the pla
2017年NPR美国国家公共电台12月