11.   Moreover, astronomers increasingly see cometary ices as bearing the chemical precursors of life.

12.   Some amateur astronomers have already seen the comet with the unaided eye.

13.   The astronomers see the development as a threat to their night view and are working with the landowner to ease the potential light pollution.

14.   Training their sights in other directions, astronomers saw no pattern at all.

15.   Whatever the astronomers are seeing, it is probably not a star, at least not any normal star.

16.   Whenever astronomers see new stars forming, they almost always see powerful, hypersonic streams of plasma.

17.   With the coming of telescopes, astronomers saw in Mars a planet most like Earth.

18.   And if there were hydrogen clouds bathed with ultraviolet light around distant stars, astronomers would have seen them by now.

19.   Astronomers have seen as much of the universe as they ever will.

20.   Margon said there is a physical limit on just how far back toward the big bang astronomers will see.