Electric Nature

[webolife]

Simple GC. Imagine looking at spinning lawn sprinkler when its stream is on the opposite side of the sprinkler from your perspective. In the case of comets, trails of paraticles extend backward in the path where the comet has come from, while other streams of particles [ions] stream away from the comet on the radial line from the sun [the solar "wind"]. Other particles stream out in all directions due to the electrical stress factor, producing the coma.

[webolife]

On the subject of radiation-loving extremophiles, just because a particle looks like a bacterium doesn't mean it walks and quacks like a bacterium. This is wishful thinking at best, along with the entire theory of panspermia. Hoyle and Wickramasinghe's work with and conclusions regarding interstellar organics assumed the presence of freeze-dried bacteria with a specific cystal configurations. It does not follow that if I put flour, milk and eggs in a bowl, I have pancakes.
Too many other thermodynamics defying procedures must happen before breakfast is served. This analogy of course is flawed because the complex fundamental ingredients are assumed to have preexisted.

[Grey Cloud]

Hi Webolife,
Thanks for the explanation but the lawn sprinkler is stationary whereas the comet is obviously rattling along.
I agree with you on the panspermia issue. The experts have been agreeing and then disagreeing with the theory for years. It's similar to the 'comet killed the dinosaurs' thing.

[Grey Cloud]

Hi Webolife,
Thanks for the explanation but the lawn sprinkler is stationary whereas the comet is obviously rattling along.
I agree with you on the panspermia issue. The experts have been agreeing and then disagreeing with the theory for years. It's similar to the 'comet killed the dinosaurs' thing.

Why doesn't the comet have tails all round it if the thing is spinning off the lead tail?

[webolife]

It does if you consider the coma.
The comet isn't necessarily spinning like the sprinkler... you took me too literally.
Think of a photograph of the sprinkler when it's spraying in the location I said, then slide the photograph across your view.

[Grey Cloud]

Hi Webolife,
I knew I shouldn't have started this. I'm guessing here that the ion tail is at the front? So as I see it, the ion tail has to be travelling faster than the actual comet/coma. So what is pumping out ions faster than a speeding comet? Or is the whole ion tail, coma, dust tail thing sat inside some sort of envelope?

[nick c]

Hi GC, webolife,
I would not dismiss panspermia theory so easily. The jury is still in deliberation on that one.
There are, imhop, a lot of niceties concerning panspermia that favor it over a genesis on a 'self contained and isolated from the rest of the universe' Earth. Panspermia is a general term that has many variations, combinations, and possibilities. It does not necessarily explain the origin of life but may, in certain applications, explain the origin of life on Earth. The main argument against, seems to revolve around the difficulty of transport through the hostile environment of space.
Yes, it has been around for a long time, Anaxagoras (circa 500 BC) has been proposed as the originator of the theory in a recent [url2=http://shopping.msn.com/specs/anaxagora ... mia-theory]book[/url2], and the theory has since reappeared many times.
This is one of those things that is not going to go away, as the issue is difficult to prove or disprove with the information available at this time. I would expect that some future discoveries from probes will shed some light one way or the other.

nick c

[nick c]

GC,
With regard to comet tails, the coma (head) of the comet is not necessarily moving ahead of the tail. The tail is typically pointing away from the Sun, regardless of whatever direction the comet is traveling. There are, in general, two types of tails-dust and ion. They can be pointing in differing directions, as far as comets are concerned, the word "tail" does not imply direction of travel. There really is no front or back.
I would post a link but they talk about "sublimating ices" and other such nonsense.
Try this instead:
http://www.thunderbolts.info/tpod/2004/ ... s-tail.htm

nick c

[Steve Smith]

Comets will sometimes exhibit two tails because of the ionization that occurs in the coma. Comets are, afterall, electrically charged bodies.

Ultraviolet light from the Sun can ionize the light gases in the coma, causing it to stream away from the nucleus in the direction of the "solar wind." The dusty component is less reactive to the "solar wind," so it tends to follow the orbital path of the comet.

As the comet moves around the Sun, the two tails will diverge from one another because the ion tail always points away from the Sun and the dust tail remains trailing along the orbital trajectory. The spike pointing toward the Sun is called the anti-tail, and results from the ion tail diverging by more then 90 degrees.

Comet Hale-Bopp


Comet Arend-Roland


Comet McNaught

[Grey Cloud]

Hi Steve,
Thanks, it was the relationship between the ions and the Sun which I was missing. Fantastic images BTW.

[Grey Cloud]

Hi Nick,
Your woman O'Leary is just another modern expert who is either congenitally stupid or a liar. Anaxagoras' ideas have nothing to do with panspermia and are just a variant on the regular Greek philosophy and by extension the Ancient Wisdom.
He said that Mind (nous) is the ultimate cause and

6. Other things include a portion of everything, but mind is infinite and self-powerful and mixed with nothing, but it exists alone itself by itself. For if it were [Page 241] not by itself, but were mixed with anything else, it would include parts of all things, if it were mixed with any thing; for a portion of everything exists in everything, as has been said by me before, and things mingled with it would prevent it from having power over anything in the same way that it does now that it is alone by itself. For it is the most rarefied of all things and the purest, and it has all knowledge in regard to everything and the greatest power; over all that has life, both greater and less, mind rules. And mind ruled the rotation of the whole, so that it set it in rotation in the beginning. First it began the rotation from a small beginning, then more and more was included in the motion, and yet more will be included. Both the mixed and the separated and distinct, all things mind recognised. And whatever things were to be, and whatever things were, as many as are now, and whatever things shall be, all these mind arranged in order; and it arranged that rotation, according to which now rotate stars and sun and moon and air and aether, now that they are separated. Rotation itself caused the separation, and the dense is separated from the rare, the warm from the cold, the bright from the dark, the dry from the moist. And there are many portions of many things. Nothing is absolutely separated nor distinct, one thing from another, except mind. All mind is of like character, both the greater and the smaller. But nothing different is like anything else, but [Page 243] in whatever object there are the most, each single object is and was most distinctly these things.[1]

http://history.hanover.edu/texts/presoc/anaxagor.htm
That Anaxagoras used words such as sperm, germ and seed has nothing to do with panspermia. These words crop up throughout the ancient literature - a thought can be a seed.
There does not appear to be anything in Anaxagoras that is radically different from what is in the Vedas which pre-date him by a couple of millennia at least.
Here is her CV:
http://www.semp.us/margaretoleary.php

[Steve Smith]

Panspermia belongs in the Mad Ideas section, in my opinion. It is tantamount to saying that aliens seeded the Earth, because there is not one shred of proof for the concept. Frozen waterbears or bacterial spores found in near Earth orbit do not constitute anything except affirmation of the consequent.

[nick c]

Hi Steve,

Panspermia belongs in the Mad Ideas section, in my opinion. It is tantamount to saying that aliens seeded the Earth, because there is not one shred of proof for the concept.

Agreed, the subject belongs in NIAMI.
The concept could indeed, be extended to "saying that aliens seeded the Earth." In fact this has been done:

In the early 1970s, Crick and Orgel further speculated about the possibility that the production of living systems from molecules may have been a very rare event in the universe, but once it had developed it could be spread by intelligent life forms using space travel technology, a process they called “Directed Panspermia”.[54]
http://en.wikipedia.org/wiki/Francis_Crick

It is interesting that this subject is acceptable for mainstream discussion and consideration (Crick was a former Nobel Prize winner) yet EU topics are taboo.

nick c

[nick c]

Hi GC,

Your woman O'Leary is just another modern expert who is either congenitally stupid or a liar.

Sorry to get your feathers ruffled
But O'Leary is not my woman, GC. I never have read the book, only came across the title after researching the topic of panspermia and thought it might be of interest with respect to the history of the theory.
I for one would not dare to comment on Ms. O'Leary's inherited IQ or veracity.
Whether or not Anaxogoras originated the Panspermia theory is not an essential element of my post, as it was inserted to show the idea of panspermia is an old one. Either way, it dates to at least the 18th C, and it would not surprise me that there would be an ancient precedent as seems to have been the case with most "new" ideas.

A reading of the subject reveals that O'Leary is not alone in attributing the panspermia idea to Anaxagoras, for example:

Certainly, the idea is not new in scientific circles. The philosopher Anaxagoras, in 5th century BC Athens, is the first recorded advocate of the theory of “panspermia”, the idea that life on Earth was seeded from space.
http://ougseurope.org/newsletter/articl ... permia.asp

and also:

The idea that life on Earth had an extra-terrestrial origin may be traced back to the ancient Greek philospher Anaxagoras, who lived in the fifth century B.C. Anaxagoras claimed that the universe is made of an infinite number of spermata (seeds). These give rise to life forms on reaching the earth. Anaxagoras coined the term Panspermia, meaning literally 'seeds everywhere', for his proposal.
http://www.simsoup.info/Origin_Issues_E ... Space.html

and again:

The first point, which deals with the origin of life on Earth, is known as panspermia — literally, "seeds everywhere." Its earliest recorded advocate was the Greek philosopher Anaxagoras, who influenced Socrates. However, Aristotle's theory of spontaneous generation came to be preferred by science for more than two thousand years.
http://www.panspermia.org/intro.htm

The fact that these are modern experts is irrelevant, presumably they have studied the subject and come to a conclusion, with which we can agree or disagree. We cannot devalue what someone wrote because they are a modern "expert." As you are a product of the 20th/21st C, your opinions come under the category of modern too.

nick c

[webolife]

"Modern" panspermia is a reaction to the realization, over a half century ago, that spontaneous generation of life on the earth under any conditions that could be hypothesized, has virtually no chance of success. Yet, as from the materialism thread, "here we are", so we/life must have come from somewhere else, and not only that, must have been repeatedly seeded, as from comets, over the supposed eons of time required by evolution... this very realization spawned first the mega buck flop SETI, then its offspring (native to my own alma mater the Univ of Wash) astrobiology, ie the search for conditions in the universe where life forms [extremophiles] might find possible habitation. The snipe hunt for earthlike planets is all about panspermia, despite the obvious fact that any such planets are likely to hold the same problem for spontaneous generation that our home planet exhibits. Holy shades of the church of cosmology, batman, I mean JL.