comets

I've always been curious about the number of dead long-term comets out there. dead meaning they do not outgas anymore""

WISE Bags its First Near-Earth Asteroid | Universe Today 2010

I've always been curious about the number of dead long-term comets out there. dead meaning they do not outgas anymore

WISE Bags its First Near-Earth Asteroid | Universe Today 2010

If the Oort Cloud does exist, the number of extant comets is far greater than was once believed.

The Sky Is Falling 2008

If the Oort Cloud does exist, the number of extant comets is far greater than was once believed.

The Sky Is Falling 2008

If the Oort Cloud does exist, the number of extant comets is far greater than was once believed.

The Sky Is Falling 2008

But, besides all these, there are found to occur other masses, not much bigger and some probably smaller, and these we call comets when we see them.

Pioneers of Science Oliver Lodge 1895

I would have had him teach us something of the nature of the things we call comets, or stars with large tails, and of that of the fixed stars, which we suppose to be suns, like our sun, with planets revolving round them like ours, since it is clear that they do not borrow their light from our sun, nor from anything that we can discover in the heavens.

Rambles and Recollections of an Indian Official William Sleeman 1822

There are short-term comets, called periodic comets, which reside in our solar system, and make appearances every couple of years.

Vineyard Gazette - Top Stories 2009

Those that have been examined up close by space probes are about 50 percent frozen water and 50 percent rock and dust; some experts call comets dirty snowballs.

Earth contains a vast amount of water, but scientists are unsure of its origins Ben Harder 2010

Was water brought to the moon by space rocks and icy bodies called comets?

2009: A Year of Discovery and Promise in Space 2010