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Fraser
2004-May-14, 05:53 PM
SUMMARY: Approximately 250 million years ago, something nearly wiped out life on Earth; 90% of marine animals and 80% of land animals were snuffed out in the geologic blink of an eye. Researchers now believe they've found the culprit: an 8 to 11 km (5 to 7 mile) asteroid that stuck the Earth off the coast of Australia. The impact happened so long ago, there isn't a crater, but geologists have found several clues that lead to this spot, including deposits of "shocked quartz" which can only be formed in a violent event like an asteroid strike.

What do you think about this story? Post your comments below.

Binary
2004-May-15, 08:38 AM
Well if it happened once then the possibility for yet another impact is not if it would take place but when. We all know that while planets are formed there is a lot of collisions between inter planetary objects. The one between Comet Shoemaker-Levy and Jupiter in July 1994 simply shows us that there is no beginning and end to impacts, it is an ongoing process. I have now doubt that the earth has been hit hundreds of times in the past, some being small while others being large global killers. I just hope that I will not be around when the next one hits. :blink:

antoniseb
2004-May-15, 12:05 PM
Originally posted by Binary@May 15 2004, 08:38 AM
the possibility for yet another impact is not if it would take place but when.
Something has happened in the last ten or twenty years that has seriously reduced the likelyhood of an asteroid hitting the Earth again. That is, we became aware that it is possible, have taken action to identify potentially threatening rocks, and are developing the science and technology required to change a potential hit to a near miss.

Unfortunately, there are plenty of other natural and man-made phenomena that could cause mass extinctions.

StarLab
2004-May-15, 04:38 PM
Yeah, for that big Permian extinction, I've heard some crackpots dictate that that extinction was due to a drop in O2 levels. Weird!... :huh: :blink: :rolleyes: :lol:

Eric Vaxxine
2004-May-17, 04:29 PM
Pavel Smutny...isn't that Paul Sad when translated into Englis?

So, our system has been cleaned up over that last million years, and far off objects bring more space debris into our little part of the universe. That makes sense. I have no faith we could divert anything bigger than a soccerball. :(

And sometimes, I think it might take a little natural disaster to make the worlds religious factions and fanatics, capitalist buckbankers and insipid pessimists learn something new. <_<

Guest_John
2004-May-17, 07:00 PM
Planet X was hypothesized to explain orbital perterbations in Neptune. It was later found however, that those orbital perterbations vanished if the older measurements were thrown out because they were inaccurate. The new orbital calculations show no major perterbations and there is therefore no Planet X.

I cannot be cetain whether Nemesis exists, or not. I would assume that if it is a star, we would have detected it in one of the many all sky surveys recently completed. If it was a brown dwarf we would have detected it with one of the many infrared telescopes. A lack of evidence does not prove something does or does not exist...

Guest
2004-May-18, 03:56 PM
If there were dark matter inside of Sedna&#39;s orbit, especially planet-sized, we woulda detected it by now... :rolleyes: :unsure:

Duane
2004-May-18, 07:26 PM
There is no Planet X. There never was a Planet X. The new observations and measurements of Neptune were done with instruments that were far more accurate than the initial ones that found a descrepancy in Neptunes orbit.

Once the measurements were corrected to reflect the real planet and its orbit, the "descrepancies" disappeared. It is as simple and basic as that.

I am going to discuss this subject here this time only. Pavel, if you intend to discuss this subject further, then I suggest that you register and start a thread in the Alternate Theories section. If you are afraid to have your theory debated in an open forum like this one, then go away.

Ok, measurements of all of the planets&#39; orbits has been done to such a degree that a probe launched from Earth 7 years ago is going into orbit around a planet exactly when and where it was expected. If there was a so-called planet x, the gravity of that object would have affected this probe (and others like Voyager) in a measureable way. It would have required the course of the probe be altered to account for the effect of the gravity.

This is straight-forward Newtonian physics, so you don&#39;t need to try and get your head around Einstien&#39;s equations to figure it out. I don&#39;t know what "calculations" you are pretending to have done, but I suggest that if you have come up with something showing a gravitational influence in the solar system beyond what is already known, then you should go back and correct your adding errors.

If there were a Planet X, it would be well known and obvious. It&#39;s not like the idea would need to be kept secret for any reason. In my mind the idea doesn&#39;t even merit the term pseudo-science--it is, at best, junk science.

I have more sympathy for the idea of a Nemesis star or planet, although frankly that theory has been mostly disproved by real scientists doing real calculations, at least for as massive an object as a dwarf or brown star, or even down to one as small as Saturn. Again, elemental Newtonian physics.

The comments you make about the Pioneer and Voyager space-craft are simply nonsense. While there is something going on with their speed relative to the sun, these craft are all way beyond the influence of any so-called planet x. The idea that a planet near Saturn could affect them this way is laughable.

Same with your comments on why anyone would keep such a finding secret. The idea is so ludicrous it beggers my ability to respond with a modecum of politeness. To call the idea stupid is being too kind.

There is some debate about whether or not there is evidence of periodicy in mass extinction events, and there is no consensus one way or the other. The difference between that debate and the drivel you are spouting here is that there is real debate over the evidence and measureable findings supporting both sides. There is absolutely no evidence to support your suggestion--in fact, all the evidence clearly and undeniably supports the premise that there is no other major planet at least out to the Oort cloud.

A warning Pavel--I welcome and invite you to debate your pet theory in the Alternive Theories forum to your heart&#39;s content. However, having said that, if I see you continuing to try and highjack topics, I will edit or delete your posts. We do not allow the promotion of pet theories in this forum, please review the forum rules especially noting Number 6.

DippyHippy
2004-May-18, 08:01 PM
Duane&#39;s absolutely correct - you&#39;re more than welcome to discuss your ideas in the alternate theory section, but we&#39;d ask you to join first and to actively participate in other discussions across the site.

Universe Today is NOT a forum for individuals to plug their own ideas and theories, as rule No.6 states.

Lastly, please bear in mind that we can ban IP&#39;s as well as members.

Pavel Smutny
2004-May-19, 08:07 AM
Thank you for your response and for warning.
I only wanted to know, discuss something more about Cassini mission to Saturn.
When these missions are so expensive (financed from state budgets) so I think that people can know also results from these missions.
Results are not only photos of Saturn, Titan... bast also some potential deviations in motions of spacecrafts (due to PX or ???). I think that it is interesting too.
We know very well how it was with Pioneers 10, 11 and what official conclusions were done (gravitational anomaly...). I know them wery well and peple know that these conclusions are not wholy scientifical, results, data, graphs weren&#39;t given in full size to public thogh many wanted to know them...

resenmut
2004-May-21, 02:19 PM
All story about asteroid which nearly ended lif on Earth is partly disinformation.
Why?
Look on geographical map of Pacific Ocean bottom.
It seems so, that this oceanic bottom is rest for bubble which was sucked from Earths top layers (thanks to very strong gravity of some very heavy body- Planet X??) and after departure of this body from Earth&#39;s vicinity this gigantic bubble flatten.
You can see simmilar effects on asphalt bubbles on roads...
There are not older rocks than 250 millions years in whole Pacific Ocean though on continents we have rocks older than 3 billions years&#33;&#33;&#33;
Asteroid which hit Earth before 250 millions years near Australias North-East shore was only body, which accompanied PX how its satellite or body which path was changed by PX and was pointed toward Earth.
This is the most probably true version and not that one from NASA which is not complete info.

Duane
2004-May-21, 07:18 PM
Good lord, where do people come up with this stuff?

The formation of the pacific basin occured approximately 200 Million years ago as a direct result of ocean floor speading arsing from plate tectonics. There is no "bubble" and nothing could have been "sucked off" the planet, by a planet x or anything else.

Do you understand the concept of gravity? I think you might be talking about a possible tidal bulge, but there is nothing that could create such a bulge on one portion of this planet.

Continental rocks have been found which exceed 3.5 billion years because continents do not recycle into the mantle like ocean floors do. As for this:


Asteroid which hit Earth before 250 millions years near Australias North-East shore was only body, which accompanied PX how its satellite or body which path was changed by PX and was pointed toward Earth.
This is the most probably true version and not that one from NASA which is not complete info.

What are you talking about? The crater recently found near Australia evidences a impactor of about 6km across. What in heavons name has a small object like that got to do with any supposed planet x?

Shake your head, I think your eyes are stuck :P

Smutny Pavel
2004-May-22, 02:01 PM
Good lord, where do people come up with this stuff? -

--WHATT FOR STUFF DO YOU MEAN? THAT ONLY NASA PEOPLE HAVE PATENT ON WISDOM?
YOU ARE ONLY CHEATING AND KIDDING MANKIND.
STOP DO IT&#33;

The formation of the pacific basin occured approximately 200 Million years ago as a direct result of ocean floor speading arsing from plate tectonics. There is no "bubble" and nothing could have been "sucked off" the planet, by a planet x or anything else. --

THERE WAS BUBLE- TIDAL BUBLE WHICH WAS CAUSED BY SOURCE- VERY MASSIVE BODY WHICH PASSED NEXT TO OUR PLANET.
LOOK INTO SCHOOL BOOK FOR EXAMPLE GEOLOGY FOR HIGH SCHOOLS, THERE ARE MANY PICTURES OF PACIFIC BOTTOM, WHICH CLEARLY SUPPORT MY IDEA...

WHEN YOU TAKE STATISTICS, SO EVERY SOME TENS, HUNDREEDS THOUSANDS YEARS SOME STAR FROM OUR SURROUDING PASSES QUITE CLOSE TO US...
TAKE IN ACCOUNT ONLY STARS FROM 100LY OUR NEIGHBOURHOOD.
MANY OF THESE STARS HAVE SPEEDS MORE THAN 10, 20,30 KM PER SECOND TOWARD US&#33;&#33;&#33;
SMALL STATISTICS, SIMPLE CALCULATIONS AND YOU CAN SEE HOW VERY PROBABLE IS PASSING OF STAR QUITE CLOSE TO US&#33;&#33;
PRESENCE OF PLANET X IN OUR SOLAR SYSTEM IS EVIDENT AND YOU CAN FIND MANY HISTORICAL, GEROLOGICAL, ASTRONOMICAL... PROOFS FOR IT ALSO ON MY WEBS.

Senmut map, Chinese funeral astro painting, Dendera zodiac, Narmer palette, astro oriental carpets, Bible, Enuma Elish, ancient texts of many nations.... with conclusions, analyses of (PX proofs)...
Ocean water level rising, Ice glaciers probes GISP2 project, sediments analyses, Earths magnetic pole shifting, unusual floods in Central Europa, mid China, under Caucasus area in 2002 with my conclusions, computations, very often gatherings eclipses of planets in last years in suspected area of PX, perturbancies in paths of Uranus, Neptune, Saturn, inklinations of their orbits, computations for these things.. ,shifts of focuses of long periodic comets (to the left, right toward their main axis of their orbits at comets NAET, SOHO, LINEAR...from last years)
Pioners 10,11 spacecrafts slowings cases, Voyagers paths analyses
these facts and many other mean for some people simply nothing.

When there is by you proclaimed recycling of oceanic mantle so whay werent recycled rocks on oceanic bottom also after era 200 millions years BC?
Everything was recycled in one time&#33;&#33;&#33;???

antoniseb
2004-May-22, 02:54 PM
Originally posted by Smutny Pavel@May 22 2004, 02:01 PM
WHEN YOU TAKE STATISTICS, SO EVERY SOME TENS, HUNDREEDS THOUSANDS YEARS SOME STAR FROM OUR SURROUDING PASSES QUITE CLOSE TO US...
TAKE IN ACCOUNT ONLY STARS FROM 100LY OUR NEIGHBOURHOOD.
MANY OF THESE STARS HAVE SPEEDS MORE THAN 10, 20,30 KM PER SECOND TOWARD US&#33;&#33;&#33;
SMALL STATISTICS, SIMPLE CALCULATIONS AND YOU CAN SEE HOW VERY PROBABLE IS PASSING OF STAR QUITE CLOSE TO US&#33;&#33;
Pavel, first, don&#39;t shout. Use the quote mechanism to separate other&#39;s comments from your text. Second, what level of formal education in astronomy and physics do you have? I&#39;d like to be able to help explain to you why your ideas seem crazy and unsupportable to us, but it would be rude to talk to you like a child if you are not one, but useless to treat you as an expert if you aren&#39;t one.

Concerning the quoted bit above, stars very rarely pass close to us. Certainly not in the timescales you are talking about. The next &#39;close pass&#39; will be in about nine thousand years when Barnard&#39;s Star will pass a little over three light years from us. This is not close enough to make a difference to the orbits of any planets or even Sedna.

As to speeds that these objects have coming towards us, that is just one component of the velocity, they also have components that take them to the side of us. I&#39;m having a little trouble finding a reference to any star coming towards us at more than 10 kilometers per second [please supply a link to a reference for this], but even assuming a star is travelling in our general direction at 30 kps, and is 50 ly away, it will take half a million years to get to our neighborhood. This is not tens, hundreds, or thousands of years.

Pavel Smutny or Senmut Resenmut
2004-May-23, 07:29 AM
I have studied on university in Bratislava Electronics-Optics and finished that school 18 years ago...
I had devoted big effort to Astronomy connections on Egyptology, Sumerology, Geology especially in last three years...
People must take in account all spectrum of knowledge, wisdom and not to be only specified into one sort of science because they can easy lose contact with reality...
This is not easy but it is essential...

antoniseb
2004-May-23, 12:12 PM
Hi Paval,

That looks like a good education. I will come straight to the point of why we don&#39;t take the Planet X business seriously.

You must be aware that there are tables and formulas that predict the positions of the planets for observers that have been very accurate for the last hundred and fifty years. You can use the oldest of these tables to find where Saturn should be today, and it will be accurate to within about one minute of arc. Modern tables are even better, and are constructed making no assumption about an object with two percent the mass of the sun passing near Saturn.

If Planet X exists, and is where you say it is, Saturn should have been perturbed in its orbit by its gravity. By my calculations, Planet X should have slowed Saturn enough to make it more than one degree [2 diameters of the full moon] behind the position it should be in. But, a week ago I went out with my small three-inch telescope and found it exactly where the old and new charts say it should be. This can&#39;t be more than ten arc-seconds away from the expected position, and could be much closer than that.

This leads me to conclude that Planet X is either:
-not there at all
-has a mass less than five times the mass of the Earth
-has a previously unknown and unseen property that allows it to have mass, but no gravitational influence. [which I suppose is possible give than it has the mass of an M5 red dwarf, but still hasn&#39;t been seen].

If you have looked at the astronomy of the Sumerians, Chaldeans, Babylonians, and their contemporary Egyptians, you know something of how they calculated the movement of the planets [mostly just the sun and moon]. They invented some very interesting methods for interpolating. But nothing in their methods or recorded tables indicates any observation of the planets being seriously perturbed from their current orbits. Their observations do show some very small corrections were needed beyond just simply calculating each orbit as an independent two-body problem with the sun, but all are explained through the influence of the other planets integrated over time.
If they observed no unexplained perturbation, what could they have seen that would have any meaning with respect to Planet X?

Guest
2004-May-24, 07:48 AM
Ecliptical latitude (with) at Saturn for this year should change (according new almanach for this year) from -0,59 degrees in January on -0,02 in December.
Inklination for Saturn is 2,485 degrees toward ecliptic.-

We have change of Saturns position toward us and toward ecliptic plane in level
2,485 degrees per (29,4 /4) years, what is 0,338 degrees per year.

So where from is difference (0,59-0,02) - 0,338 = 0,23 degrees...?

We are much closer to Sun than Saturn and we are in ecliptic plane.
Difference 0,23 so can be with (0,3 / 1,4) = 20 % uncertainity...
(Earth orbits diameter/ Saturn orbits radius)...

Where is number 0,23 degrees from, if not from X?

antoniseb
2004-May-24, 10:16 AM
Originally posted by Guest@May 24 2004, 07:48 AM
Where is number 0,23 degrees from, if not from X?
Did you measure this yourself? I did, and found Saturn exactly where it is supposed to be [within my limits of observation [about 10 arc-seconds]]. I suspect that whoever told you that Saturn has moved off course by 0.23 degrees has not actually observed Saturn, and if they claim they did, they have lied.

Smutny Pavel
2004-May-24, 01:50 PM
How is it with data in astronomical almanachs?_
There are (in charts, tables) foretold positions of planets for this year...
These data are based on computations from real data, positions of planets from previous 1,2,3... 300 years, from previous cycles and from known data about planets orbits, periods...
They compare data from previous cycles and orbits done by planets with present (1,2,3...years old measurements on sky)..., they give (as a results) to us predictions for positions of planets.
But if there don&#39;t exist Planet X so change of Saturns position toward ecliptic (on sky) should be 2,485degrees/(29,4/4) what is 0,338 degrees per year +-20 percent.

Why is it not so?&#33;

Give me exact data from american astronomical almanachs for Saturn for this year and old data 1,2,3...100 years old.
We can compare them and say more...

Smutny
2004-May-24, 02:04 PM
Important is to compare predicted, real positions of Saturn from 1974,1975, when Saturn was exactly one orbit backward on relatively the same place on sky toward us (how it is now).
...

Smutny
2004-May-24, 02:07 PM
Important is to compare predicted, real positions of Saturn from 1974,1975, when Saturn was exactly one orbit backward on relatively the same place on sky toward us (how it is now) with present data predictions...
...

Duane
2004-May-25, 03:59 PM
--WHATT FOR STUFF DO YOU MEAN? THAT ONLY NASA PEOPLE HAVE PATENT ON WISDOM?
YOU ARE ONLY CHEATING AND KIDDING MANKIND.
STOP DO IT&#33;


Please Pavel, you don&#39;t need to shout at me :)

Stuff like the accidental positioning of the continents in a sort of "ring" as a result of millions of years of plate tectonics, thus forming the Pacific basin. This has nothing to do with a tidal bulge, or the formation of any kind of "bubble" from a passing object of any kind.

Furthermore, a tidal bulge would not arise in only one area of the planet--it would change position as the planet rotates. A good example of this is Io&#39;s tidal bulge.

NASA has a patent on wisdom? Unfortunantly not&#33; A little more wisdom would be a good thing for NASA. However, knowledge and wisdom are not ithe same thing, and NASA has a great deal of knowledge arising from some very knowledgable people.


THERE WAS BUBLE- TIDAL BUBLE WHICH WAS CAUSED BY SOURCE- VERY MASSIVE BODY WHICH PASSED NEXT TO OUR PLANET.
LOOK INTO SCHOOL BOOK FOR EXAMPLE GEOLOGY FOR HIGH SCHOOLS, THERE ARE MANY PICTURES OF PACIFIC BOTTOM, WHICH CLEARLY SUPPORT MY IDEA...


Come on Pavel, surely you can provide a better argument than "it looks like that"? In a few tens of millions of years, the Atlantic ocean will look more like the Pacific does now, as the continental plates are converging towards the Pacific basin, shrinking it by a few meters every year. Again, it&#39;s the accidental placement of the continents today that invokes the illusion that the Pacific basin is circular.

Were you aware that proponents of the theory that the moon came from the Earth suggested the Pacific basin as the area from which the moon arose? Again, they looked at maps of the Earth, saw the circular appearance of the Pacific basin and said "viola&#33;". Then plate tectonics were discovered....


Ocean water level rising, Ice glaciers probes GISP2 project, sediments analyses, Earths magnetic pole shifting, unusual floods in Central Europa, mid China, under Caucasus area in 2002 with my conclusions, computations, very often gatherings eclipses of planets in last years in suspected area of PX, perturbancies in paths of Uranus, Neptune, Saturn, inklinations of their orbits, computations for these things.. ,shifts of focuses of long periodic comets (to the left, right toward their main axis of their orbits at comets NAET, SOHO, LINEAR...from last years)
Pioners 10,11 spacecrafts slowings cases, Voyagers paths analyses
these facts and many other mean for some people simply nothing.


Sorry Pavel, maybe it&#39;s a language thing, but I am not entirely sure what you are trying to say here.

So ocean levels appear to be rising as a result of global warming. I don&#39;t see how or where you think that has anything to do with a supposed Planet X.

Yes the magnetic field of this planet changes periodically, on a time scale of a few thousand to a few tens of thousands of years. So what? And what does that have to do with a Planet X?

On orbital perturbancies, to be blunt, you don&#39;t know what you are talking about. Even using your own comments about ancient astronomers, many of the maps and plots they used have been studied and compared to modern day measurements, and their positioning of the planets was found to be amazingly accurate. If there was another massive body, there would be evidence that their positioning of orbits would be off--yet that is not the case. The Mayans, Arabs, Chinese, Greeks and others all observed and plotted the planetary orbits of the naked eye planets, including Saturn, and in many cases they plotted the orbits forward to today and beyond correctly.

As Antoniseb says, no descrepancies in the orbits when you go to look.


When there is by you proclaimed recycling of oceanic mantle so whay werent recycled rocks on oceanic bottom also after era 200 millions years BC?
Everything was recycled in one time&#33;&#33;&#33;???


Short answer is they are being recycled constantly. Again, looking at the maps of the Pacific basin, note that the basin is surrounded by subduction zones. Ocean basins arise and subduct constantly over a period of millions of years.

The theory of a Planet X is bunkum, pure and simple.

Oh, and education is not necessarily a sign of wisdom either.

Comet Temple 1 & Sedena
2005-Apr-21, 01:39 PM
Comet Tempel 1 will only be 83 million miles from Earth when rendezvous is accomplished and the impactor is launched and detonates on July 4, 2005. That is roughly the longest distance from Earth to Mars, the average distance from Earth to MercuryComet Tempel 1 is also currently positioned in the inner solar system -- between Earth and the Sun, like Venus and Mercury.

The Nasa site also said the energy from this impact will be observable with the naked eye from some places on earth, but didn&#39;t specify the locations or even which hemisphere. Obviously, everyone will see it on television, since Deep Impact, Chandra, Hubble, and another satellite telescope will be sending images back to earth.

We saw Jupiter and we saw the explosions, but we never saw each individual fragment as it slammed into Jupiter. Hubble, Chandra, and earth-based telescopes will not be able to discern either Deep Impact or the impactor, only the comet and the explosion. As for what people on earth will see with their own eyes, in those locations that are favourable, there should be a sudden flash of light and possibly a temporary glow.

The thinking here is 2 seperate comets different course.

Also I think Sedena the new Planetoid object is moving thru the belt. I wonder if it has enough pull on it&#39;s cycle thru to awaken a dormat comet or asteroid.