The age of comets

California's Channel Islands hold evidence of Clovis-age comets July 20,This map shows California's Channel Islands with the islands of the previously combined islands of Santarosae encircled at the top. Courtesy NOAA and UC Santa Barbara A member team has found what may be the smoking gun of a much-debated proposal that a cosmic impact about 12, years ago ripped through North America and drove multiple species into extinction. In a paper appearing online ahead of regular publication in the Proceedings of the National Academy of SciencesUniversity of Oregon archaeologist Douglas J.

The age of comets

All comets would have disintegrated after 10, years. Jupiter and Saturn wreak havoc to the comet orbits. Some long-period comets are perturbed into short period orbits, others are permanently ejected.

Comets are believed to have a short lifetime after being perturbed to short periods.

The age of comets

Actually, the Oort cometary cloud hypothesis published by Jan H. Oort in was originally proposed in order to explain "the rate of appearance of long-period comets" i.

However, the fact that a comet cannot have occupied its present orbit for very long does not automatically imply that it is young. The Oort hypothesis does explain this problem as well, in that long-period comets -- if frequent enough -- will be moved into short-period orbits by a relatively near approach to a planet comet loses momentum, planet gains it, comet is now in a vastly shorter orbit, planet is now in a very slightly longer orbit.

In fact, of the short-period comets, roughly half orbit pretty much between the sun and jupiter, leading astronomers to believe that jupiter "captured" them into their current orbits.

Statistically, we would expect the largest planet -- the best "capturer" -- to have captured the most short-period comets.

Finally, nobody really knows about the Oort cloud. Astronomers like the way it explains the frequency of long-period comets, and there is much support for it amongst them. It apparently also explains the youth of the short-period comets, quite nicely. However, until we see a comet get sucked into a short-period orbit apparently this must happen every years or soor until we send something out to 10, A.

Actually the premise is false. The Sino-Tibetan family of languages is distinct from the Indo-European family of languages, which English seems to have been derived from.

Considering how long ago the 50 arguments were written was it around ? Ever heard of plate tectonics? Your county Soil Conservation Board will be happy to tell you why your topsoil is getting shallower, and what you can do to curb the problem.

Comet - Wikipedia

Mississippi delta would have formed in years. You have given a steady-state system which it is NOT identified a possible geographic feature less than 5k years old. And how did you get the "original precipice" without deciding up front how old you wanted it?

Before that, the whole area was under glacial ice! And it some millenia after the ice retreated for the land to reach its present level and the drainage paths to reach their present alignment.

Not enough dissolved minerals in oceans. Dissolved minerals - the stuff moves in cycles, and as such most of the minerals are very close to their balance levels.

The same general idea holds for everything else. Remember the space shuttle? Except for the last time, it has been landing on salt. Like from the oceans, remember? Other "geological clocks" that suggest a "young" earth- juvenile water from volcanoesoil deposit pressure, Stalactite Growth limestone Juvenile water is covered in those same computer models, and again nothing tricky is involved at all.

Oil deposits themselves require a time well over years to exist, so try again. Stalactite growth - of some, perhaps. You are still identifying merely temporary features Please read: It has been devoted almost entirely to the physics of the polonium halos, thereby neglecting the geological setting of the samples in which the halos are found.

Halley's Comet - Wikipedia

As an alpha particle nears the end of its path and slows, it causes disruption of the crystal structure leaving a small damage track.The ice buried inside comet 67P/ Churyumov-Gerasimenko is mainly found in crystalline form, which implies that it originated in the protosolar nebula and is therefore the same age as the Solar System.

It really didn't have anything to do with the age of short-period comets (which the note above refers to).

[Long-period > yrs, short-period. The Age of the Earth and the Formation of the Universe Honors Seminar (UHON ), Fall Professor Timothy H. Heaton Several young-earth creationists have made the claim that comets provide a clue that the solar system, and consequently the Earth and the universe, are young.

Faulkner, D. Comets and the Age of the Solar System. TJ. Below you’ll find introductory information on the Younger Dryas Impact, including comets, diamonds, mammoths, the mysterious “black mat”, and more. Three Puzzling Ice Age Mysteries 12, years. First measurement of the age of cometary material Date: February 26, Source: DOE/Lawrence Livermore National Laboratory Summary: Though comets are thought to be some of the oldest, most.

It really didn't have anything to do with the age of short-period comets (which the note above refers to).

[Long-period > yrs, short-period.

Halley's Comet - Wikipedia