It's probably a good thing that sound cannot travel through a vacuum, for we are thus limited to earth-made sound.
声音不能通过真空传播，这也许是一件好事，因为这样我们就只能听到地球上的声音。
2
Continued bombardments and internal pressures made the growing Earth hotter, causing its interior to melt and the heavier elements to sink and form Earth's core.
持续的轰击和内部压力使成长中的地球越来越热，导致其内部融化，较重的元素下沉形成地核。
3
If it had hit the Earth, it would have made a crater 100 miles across and thrown up an immense cloud of dust.