The Hubble telescope orbits about five hundred fifty kilometers above Earth.
哈勃望远镜轨道位于地球上方550公里左右。
It shares this with a number of smaller asteroids whose orbits suggest they were spalled off in the collision, and with about 5% of the meteorites which fall to Earth.
灶神星和许多更小的小行星共同具有这种特征谱。这些更小行星的轨道表明它们是那次碰撞中剥落下来的，而其中大约5%的陨石落到了地球上。
They don't happen often-only about once a year-since the tilted orbits of the sun, moon, and Earth make their alignment rare.
它们并非经常发生，大约只有一年一次，因为太阳，月亮的轨道相互倾斜，它们很少能排成一条直线。
They say they have strong evidence for another planet in the same system that has about eight times the mass of the Earth and orbits every 84 days.
他们说他们有足够证据证明在同样系统内还有一个行星，体积为地球的8倍，运转周期为84天。
This means that as the Moon orbits Earth its distance varies from about 221, 000 to 252, 000 miles.
这意味着月球环绕地球的就是在221 000英里到252 000英里之间。
That's what a French team did for the planet Gliese 581d, which orbits a red dwarf star about 20 light-years from Earth.
一个法国团队就对就对格雷司581d行星这样做过，这个行星环绕着距离地球20光年的一颗红矮星运转。
It shares this with a number of smaller asteroids whose orbits suggest they were spalled off in the collision, and with about 5% of the meteorites which fall to Earth.
一些更小的行星也具有这样的光谱，从它们运行的轨道来看，它们是灶神星在碰撞中的脱落物，拥有的陨石数量约是落到地球表面陨石数量的5%。
Typically they move in geosynchronous orbits about 22,300 mi (35,900 km) above the earth and operate at frequencies near 4 gigahertz for downlinking and 6 GHz for uplinking.
典型的通讯卫星位于地球同步轨道，约在地球上方35，900公里处，操作频率向地传输4吉赫，向上传输为6吉赫。
The alien world, about the size of Saturn, is frigid and inhospitable. It orbits two stars 200 light-years from Earth.
这个陌生的星球如土星般大小，极度寒冷并且不适宜居住。它在离地球200光年外的地方绕两颗恒星运行。
The alien world, about the size of Saturn, is frigid and inhospitable. It orbits two stars 200 light-years from Earth.
这个陌生的星球如土星般大小，极度寒冷并且不适宜居住。它在离地球200光年外的地方绕两颗恒星运行。
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