SSS 2011-02-01
时间:2019-01-08 作者:英语课 分类:Scientific American(二)月
This is Scientific American’s 60-Second Science. I’m John Matson, Got a minute?
Imagine a pinball machine on multi-ball mode—only the balls are the size of planets. The early solar system was such a rough-and-tumble place.
That chaotic 1 environment produced the occasional literally 2 Earth-shattering collision. The moon, for instance, is believed to have formed from debris 3 stirred up by a Mars-size object careening into our young planet.
Now, new research indicates that Pluto 4 may have suffered a similar fate. According to planetary scientist Robin 5 Canup, all three of Pluto’s satellites could trace back to a single impact.
An impact has long been suspected for the birth of Charon, the largest Plutonian moon, but Canup ran impact simulations to show that Nix and Hydra 6, two much smaller satellites discovered in 2005, may be debris from the same collision. Her study appears in The Astronomical 7 Journal.
A simulated low-speed crash between comparably sized planetoids yields a Pluto and a Charon, plus an icy debris disk that could coalesce 8 into a Nix and a Hydra. That means that the small satellites should still be pretty icy—a prediction that may be tested as soon as 2015, when NASA’s New Horizons probe reaches the area. If the probe finds that Nix and Hydra are mostly ice, it'll show Canup’s simulation to be a smashing success.
- Things have been getting chaotic in the office recently.最近办公室的情况越来越乱了。
- The traffic in the city was chaotic.这城市的交通糟透了。
- He translated the passage literally.他逐字逐句地翻译这段文字。
- Sometimes she would not sit down till she was literally faint.有时候,她不走到真正要昏厥了,决不肯坐下来。
- After the bombing there was a lot of debris everywhere.轰炸之后到处瓦砾成堆。
- Bacteria sticks to food debris in the teeth,causing decay.细菌附着在牙缝中的食物残渣上,导致蛀牙。
- Pluto is the furthest planet from the sun.冥王星是离太阳最远的行星。
- Pluto has an elliptic orbit.冥王星的轨道是椭圆形的。
- The robin is the messenger of spring.知更鸟是报春的使者。
- We knew spring was coming as we had seen a robin.我们看见了一只知更鸟,知道春天要到了。
- Let's knock down those hydras and drive them to the sea!让我们铲除祸根,把他们赶到大海去!
- We may be facing a hydra that defies any easy solution.我们也许正面临一个无法轻易解决的难题。
- He was an expert on ancient Chinese astronomical literature.他是研究中国古代天文学文献的专家。
- Houses in the village are selling for astronomical prices.乡村的房价正在飙升。