【新朋友】点击标题下面蓝字【可可英语】加关注【老朋友】点击手机右上角图标【转发分享】内容听力文本This is Scientific American's 60-second Science, I'm Steve Mirsky.Happy New Year! And if you've been away from work for a few days, you deserve some time off. After all, you've traveled far—even if you just stayed at home. According to NASA, just by being on the planet Earth in the last year, you've zipped about 584 million miles around the sun, at an average speed of about 67,000 miles per hour.(CLIP: Siren sound)Hey, I wasn't speeding—in my inertial reference frame.Of course, the trip was not a perfect circle. As Kepler showed, the Earth's orbit is an ellipse, with the sun at one of the two focal points. He also figured out the planet goes faster when it's at perihelion, nearer the sun, than when it's at aphelion, its furthe
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