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Researchers: Many Black Holes in Center of Milky Way Galaxy Astronomers say the center of our galaxy has plenty of strange, super gravity objects. For years, scientists believed that circling the center of galaxies, including our own Milky Way galaxy
2018年VOA慢速英语(四)月
This is Scientific American's 60-second science. I'm Carrie Haphgn. Just take a minute. It's tough to have a job with the bosses always riding you. That's literally the case with horse. Now a study finds that the stress experience by the acquire s co
Scientific American(五)月
Remember seesaws? Those things were great. But there was often a problem. Suppose theres a big kid on one side and a smaller kid on the other side. The seesaw just stays in one position: big kid on the ground, smaller kid up in the air. No fun. After
英语听力文摘 English Digest
Theres a simple way to figure out where the center of mass is. If the big kid is two times as heavy as the little kid, then their mutual center of mass will be two times closer to the big kid than to the little kid. Three times heavier and the center
英语时差8，16
Remember seesaws? Those things were great. But there was often a problem. Suppose theres a big kid on one side and a smaller kid on the other side. The seesaw just stays in one position: big kid on the ground, smaller kid up in the air. No fun. After
英语时差8，16
Remember seesaws? Those things were great. But there was often a problem. Suppose theres a big kid on one side and a smaller kid on the other side. The seesaw just stays in one position: big kid on the ground, smaller kid up in the air. No fun. After
英语听力文摘 English Digest