Democratic Sentinel, Volume 3, Number 12, Rensselaer, Jasper County, 2 May 1879 — Comets. [ARTICLE]

Comets.

What comets may really in structure and character be, remains almost as difficult confidently to state as it was two centuries ago. That they are not solid masses every one is agreed. It seems probable that even the nucleus, when brightest and apparently most condensed, is, if a single body, a quantity of glowing gas, not a solid or even a liquid substance. It is remarkable that not only the tail, so called, but even the nucleus itself, is, as a rule, so thin that a bright star can be seen through it scarcely dimmed. What the tail may be is even more perplexing than the ques-

tion of what the head and nucleus of the comet may consist. The tails have sometimes extended over more than a quarter of the heavens; that is to say, have reached from the zenith to the horizon, and from their ascertained distance have been calculated to occupy a length of not less than 90,000,000 miles, or very nearly the distance of the earth from the sun; so that when the head of the comet was passing the sun in his immediate neighborhood, the extreme end of the tail might be almost in the immediate vicinity of our planet.