Terrestial Impact cratering distrubution

Good day ATS .

The impact cratering of the moon is obvious for all to see. Dating the craters on Luna is extremely difficult and plotting distribution versus orbital data nearly impossible. This is not the case on Earth. While there are many known impact craters dotting the Earths crust, there remain an unkown amount of undiscovered craters yet to be found.



I propose that there is a method to predicting the likelihood of future impact by looking at the craters already dotting our planet.




Here goes the theory ( or hypothesis as the casee may be ):

Look at all the known impact craters on the planet. Date them. Take the dates and figure the orientation of Earth in our orbit. Our proximity to our stellar neighbors, our aphelion, or perihelion as the case may be. Look for correlations between cometary and asteroidal orbital parameters, review orbital encounters with meteor streams ( IE Taruids, Geminids, etc..) , take into account precession and basically examine each crater as it would have been at the time it impacted Earth. Take into account the orientation of the moon to the Earth at the times of impact concluding , rightfully so I have no doubt that the moon has saved our skin on many more than one occassion. Plot the gas giants locations in relation to known cometary orbits.








Take into account impact orientation of each crater, declination and angle of impact, calculate velocity of impactor and plot data against timeframe with Earths orbital parameters on one axis , and impact orientation on another axis. Follow this course untill all of the impact craters have been " traced " and plotted back to the original time of impact .

www.lpi.usra.edu...

By doing this one could see from what direction in space impact threats are most likely to come and at what time during our orbit around the sun are we more at risk.

It may well prove that the impacts are random and come from different parts of space each time, that the whole effort was a waste of time , and that nothing conclusive can be derived from the data sets. However I think the data will show a relative risk increase factored with Earths orbit, that of the gas giants, and the moon.

This information may be used as risk indicators as we travel through space. An area of space for our telescopes to concentrate on when we approach a " hazardous " zone. To my knowledge this has never been done.

Anyone want to help?


LINK: www.qrg.northwestern.edu...


LINK: www.lpi.usra.edu...

Alias Jones

Very interesting Alias, for sure. If we could plot this to assess risk, then yeah we might be able to increase the chances that we could discover an incoming asteroid before it hit the planet. And I guess that is a great thing, but in reality, what could be done to counter it even in such a case? I mean will 100 nukes fired at a large one really do enough damage to stop the threat? Or a space-based laser of some type?

I suppose this really boils down to if we are doomed from such an event (which we probably are sooner or later), would you really want to know? Would the world really want to know? Would the discovery of such an incoming, extinction level asteroid ever be made public? If so, I think the resulting chaos wouldn't be worth it. Bang. It's over. I don't really want to know. Let me live my life to the end without the fear. Just my -$.02. But thanks very much for that!

True American I hear what you are saying.

Extinction level events may not be avoidable. With enough time I do believe some mitigation is possible, but alas our technology is in its infancy when it comes to defending the planet from killer comets or large asteroids.

I speak not of planet killers, but rather regional killers, say asteroids of Tunguska size or a little larger . Impactors that woud destroy large areas and adversley affect localized biology, not necessarily worldwide cataclysm.

I remember last year an asteroid barely missed Earth and we didnt know about until AFTER it passed us. Its threats like these , that if we had a chance , we might be able to do something about.

If the effort was put forth and a city saved, I think it would be well worth it.


Alias Jones

Yes Alias, I couldn't agree more. You have to be able to spot the target before you can kill it, and certainly your proposed plot could aid in that identification. Especially for less threatening asteroids. But even if one life is saved, this would be well worth it. Very cool article man.

Originally posted by Alias Jones
Take into account impact orientation of each crater, declination and angle of impact,

But how do you do that?

Cool thread, BTW.

The toughest part is accounting for all the changes that go on.

The earth's crust changes, the rotation changes, and all the impacts have been over a long period of time.

I really don't see this as something calculable given the time frame and rate of change, but its an awsome idea.

Loam

The impact orientation can be deduced by a couple of factors.

Ejecta patterns come to mind first - the ejecta being farthest away showing the general line of impact. Ejecta patterns should shed light on angle of impact and declination.

Knowing the material into which the impact took place ( ie limestone, granite etc.. ) and the depth of the crater would give you size and velocity.

Also and fracturing of localized terrain could shed light on the original orientation

a few udeas - anyone have any others ?

Alias Jones

Quest

I never said it would be easy - thats what computer models are for. I know that the surface of Earth is ever changing - that being the reason so many impacts will forever remain unknown. However , the orbit of Earth with regard to timeframes may shed some light on dataing the craters, carbon 14 for sure, radioactive decay of remnants of the impactor possibly, localized fossil record both geological and biological also could assist in pinpointing the strike date.

Alias Jones


[edit on 29-9-2005 by Alias Jones]