美国有线新闻 CNN 加拿大阿尔伯塔省上空出现明亮流星（在线收听）

This week there were more than 400 reports of fire in the sky. They were mostly concentrated in and around Alberta, Canada though the meteor was also visible in other parts of that country and in the U.S. state of Montana. Thanks in large part to surveillance and doorbell cameras, the American Meteor Society received more than 100 videos of this. The thing was so bright it was classified as a fireball. According to NASA that means the rock could have been bigger than three feet in diameter. It's a shocking celestial sight that looks really cool as long as it doesn't hurt anything. And as far as we know it didn't.

本周有400多起有关空中火球的报道。这些报道主要集中在加拿大阿尔伯塔省及其周边地区，不过在该国其他地区和美国蒙大拿州也能看到这颗流星。美国流星协会收到了100多个相关视频，这在很大程度上要得益于监控和门铃摄像头。这个物体非常明亮，被归类为火球。美国国家航空航天局（简称NASA）表示，这块岩石的直径可能超过3英尺。这是一种令人震惊的天体景象，它看起来很酷，只要不伤害任何东西。而据我们所知，它确实没有对任何东西造成伤害。

Scientists believe it was just a meteor not a meteorite. What's the difference? There are a lot of small rocks that are zinging through space. They're called meteoroids. If one of these rocks hit's the earth's atmosphere, it becomes a meteor. That's also known as a shooting star. The streaks you see across the sky are the result of meteors burning up in our atmosphere. Researchers say more than 90 percent of them burn up completely. If they don't do that though, if part of the rock survives its entry and smacks into the earth's surface, it's then classified as a meteorite.

科学家认为那只是一颗流星，并不是陨石。二者有何区别？有许多小岩石在太空中穿梭。它们被称为流星体。如果其中一块岩石撞上了地球大气层，它就会变成流星。Shooting star是流星的另一种说法。大家看到的划过天空的光迹是流星在大气层中燃烧的结果。研究人员表示，超过90%的流星会完全燃烧。如果没有完全燃烧，如果岩石进入大气层后有部分残留，它就会撞击地球表面，这部分被归类为陨石。

Thousands of tiny meteorites strike the earth every year but as far as we know the one seen this week in Canada wasn't one of them. It's believed to have been a meteor. There haven't been any fragments reported from the earth's surface. Initially scientists didn't know how big it was, how fast it was moving and what it was made of but they're able to piece together some information about it based on the multitude of different recordings taken from different cameras in different locations.

每年都有成千上万颗小陨石撞击地球，但据我们所知，本周在加拿大看到的那颗并不是其中之一。据信那是一颗流星。目前没有地球表面出现碎片的报告。起初，科学家不知道它的尺寸、移动速度以及组成，但他们能够根据不同地点不同摄像机拍摄的大量不同记录，拼凑出一些有关它的信息。