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Topic: Coincidence of meteor strike and close asteroid approach at same time.
Replies: 36   Last Post: Oct 4, 2013 6:26 PM

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 Robert Clark Posts: 68 Registered: 12/13/04
Re: Coincidence of meteor strike and close asteroid approach at same time.
Posted: Mar 7, 2013 9:20 AM

On Mar 6, 5:03 pm, bob haller <hall...@aol.com> wrote:
> On Mar 6, 12:27 pm, Robert Clark <rgregorycl...@yahoo.com> wrote:
>

> >  Assuming comet C/2013 A1 misses Mars by 37,000 km how much delta-v
> > would you need to nudge it to hit Mars?

>
> > This might not be purely of academic interest. Already we've seen two
> > Earth encounters whose likelihood together was one in hundreds of
> > millions.

>
> > This comet to make a close encounter to Mars is *huge*. To put it
> > perspective it dwarfs the asteroid that destroyed the dinosaurs. Such
> > close encounters to any of the terrestrial planets must be very rare.

>
> > For instance the puny, in comparison, asteroid 2012 DA14 would be
> > expected to get so close to the Earth once in 40 years. That such a
> > large comet would get so close to Mars must be much rarer than this.
> > So the chance is less than 1 in 40 in a year. Say it happens for
> > either of two planets; that's a chance of less than 1 in 20 in a year.
> > Say then it happens within a 2 year period; that's 1 chance in 10.

>
> > Now the chance of the three encounters occurring within such a close
> > time span is greater than one in several billion. The unlikelihoods
> > begin piling up greater and greater.

>
> > Then we are left with the disturbing possibility there is a physical
> > phenomenon causing these large, close encounters. And the possibility
> > arises there is another large, close encounter to the Earth that may
> > be upcoming.

>
> > It would really become important to know then not what's the delta-v
> > needed to turn a close miss to an impact, but in fact the reverse.

>
> > Bob Clark
>
> Well aiming hazardous comets and asteroids at mars or other planets
> may be a good way to get rid of hazards....
>
> theres a theory the earth has a planet killer type event every 34
> million years or so. A couple weeks ago I posted we may be entering a
> littered part of space.

http://pubs.giss.nasa.gov/docs/1985/1985_Stothers.pdf

This proposes oscillation of the Sun about the galactic plane over
time scales of millions of years as the cause. Other possible causes
described here:

http://en.wikipedia.org/wiki/Extinction_event#Patterns_in_frequency

Bob Clark

Date Subject Author
2/19/13 Robert Clark
2/20/13 David Bernier
2/20/13 Richard Tobin
2/20/13 Jeff Findley
2/20/13 Robert Clark
2/20/13 Robert Clark
2/23/13 Robert Clark
2/23/13 Robert Clark
2/27/13 Robert Clark
2/28/13 Robert Clark
10/3/13 David Staup
10/3/13 Mike Collins
10/4/13 David Staup
10/4/13 Mike Collins
2/28/13 Davoud
2/28/13 Robert Clark
2/28/13 Greg \(Strider\) Moore
3/6/13 Robert Clark