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- Light travels about 300,000 kilometers per second. 光的速度大约每秒三十万公里。
- Some galaxies recede from us at 1,000 kilometers per second, others (those twice as distant) at 2,000 km/s, and so on. 有的星系以每秒1000公里的速度远离我们，有些（距离两倍远的那些）则是每秒2000公里，以此类推。
- Some galaxies recede from us at1,000 kilometers per second, others( those twice as distant) at2,000 km/ s, and so on. 有的星系以每秒1000公里的速度远离我们，有些（离两倍远的那些）是每秒2000公里，以此类推。
- The filaments are expanding into space at a speed of roughly 5, 000 kilometers per second. 这些纤维状星云物质以每秒大约5000公里的速度向宇宙空间扩展。
- A light-year is the distance light travels in one year at a speed of 299, 792 kilometers per second. 一光年是光以每秒299792公里的速度在一年中所走过的距离。
- A mixture of liquid hydrogen and liquid oxygen produces an exhaust with a speed as high as five kilometers per second. 液态氢和液态氧的混合物产生的排气速率高达每秒5公里。
- Light travels in space at a speed of about 300000 kilometers per second,and this figure has been proved correct in a number of different ways . 光在空间约以每秒30万公里的速度传播，这一数值已被用多种不同方法证明是正确的。
- Light travels in space at a speed of about 300000 kilometers per second, and this figure has been proved correct in a number of different ways . 光在空间约以每秒30万公里的速度传播，这一数值已被用多种不同方法证明是正确的。
- If it was born at the center, as is likely, then it must have recoiled with a velocity of about 1,000 kilometers per second at birth. 假使它如大家所料的一样诞生在中心，那麽它在诞生的刹那，就必须以每秒1000公里的速度弹射出去。
- When an earthquake occurs, it generates an expanding wavefront from the earthquake hypocenter at a speed of several kilometers per second. 这个地点会告诉我们，到底发生了什么和哪里破坏最严重？
- Simulations predict that galaxies, pulled together by gravity, should buzz around at closer to 500 kilometers per second. 藉由模拟的预测显示，星系在重力的吸引下，会以每秒500公里的速度聚集在一起。
- The combined image unveils a bubble-shaped shroud of gas and dust that is 14 light years wide and is expanding at 4 million miles per hour (2,000 kilometers per second). 合成图揭示了气体和尘埃组成的泡状覆盖物，宽14光年，以每秒400万英里（每秒2000公里）的速度膨胀。
- Fluorescing in ultraviolet light, the cast off material trails behind the giant star as it plows through the surrounding interstellar medium at 130 kilometers per second. 在巨星后方的抛出物质以每秒130公里的速度穿过周围的星际介质，并且这些物质在紫外光线下发出荧光。
- The interstellar dust grains struck the aerogel at high speeds of up to 26 kilometers per second (16 miles per second) and embedded themselves within this ultralight material. 星际尘埃微粒以最快每秒26千米的高速撞上并嵌入这种极轻的物质之中。
- The comet dust is vaporized as it enters the atmosphere at upwards of 60 kilometers per second, producing visible trails that begin at altitudes of around 100 kilometers. 这颗彗星尘埃以每秒60多公里的速度闯入地球大气层，在大约100公里的高空开始产生肉眼可见的光迹。
- The temperature at Earth's exobase oscillates but is typically about 1,000 kelvins, implying that hydrogen atoms have an average speed of five kilometers per second. 地球外气层底的温度是不断变动的，不过通常约是1000K，使得氢原子平均的速度为每秒5公里。
- It travels thousands of miles per second. 它一秒钟能走几千英里。
- A unit of frequency equal to one cycle per second. 赫兹频率的单位，等于每秒一周
- The velocity of light is about 186,000 miles per second. 光速大约是每秒十八万六千英里。
- Middle C is equivalent to 256 vibrations per second. 中央C音相当於每秒钟振动256次。
