[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: More Martian Meteorites Coming this Way!

Hi Bernd and all,

>>Venus ejecta is mostly reaccreted by Venus, but a significant fraction (about 
30%) falls on the Earth ... The larger planets, Venus and Earth, thus readily 
exchange ejecta. The larger planets, Venus and Earth,thus readily exchange 
ejecta. Earth ejecta is also mainly reaccreted by the Earth but about 30% strike
Venus ...<<

I'm not sure about those figures and I'll tell you why. There are two reasons 
why we should have fewer meteorites from Venus than we supply Venus with. First 
reason is Venus has an atmosphere that is about 100 times more dense than our 
own due to the "greenhouse" effect there. That means it would take much more 
effort to leave that planet. Second it is easier for an object (meteoroid) to 
lose energy than it is for it to gain energy. So the most likely direction for 
material to fall would be "in" towards the sun. More often than gaining energy 
and moving out from the Sun. Stop a planet in its orbit and it will fall toward 
the center of gravity of the Sun. Increase the velocity around the Sun and it 
will move out to a further orbit.

It would be easier for Earth material to lose energy and become a permanent 
fixture on Venus, Mercury or fall into the Sun. Also with the super hot terrain 
on Venus I'm not too sure that it would help to dampen the incoming impactor 
and further make it more difficult to leave the planet.

I know that you might have picked up this information from a good source but 
could the source be outdated or have ignored planet dynamics in the modeling?
In any case I would be eger to hear yours or others comments on this swapping 
of debris.


List Archives are located at http://www.meteoritecentral.com/list_best.html
For other help, FAQ's and subscription info and other resources,
visit  http://www.meteoritecentral.com/mailing_list.html