What is the rate of ejecta deposited between planets?

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SUMMARY

The discussion centers on the estimated rate of meteoritic ejecta from Mars and other celestial bodies impacting Earth. It is established that approximately 500 kilograms of Martian rocks land on Earth annually, while the total meteoritic material is estimated at 50,000 tonnes per year. Participants express skepticism regarding claims of "billions of tons" of ejecta and emphasize the need for credible sources, such as the Scientific American article referenced. The conversation highlights the complexities of planetary ejecta dynamics and the factors influencing these estimates.

PREREQUISITES
  • Understanding of planetary geology and impact mechanics
  • Familiarity with meteoritic material classification
  • Knowledge of scientific literature search techniques, particularly Google Scholar
  • Basic comprehension of density and volume calculations in a planetary context
NEXT STEPS
  • Research the mechanisms of planetary ejecta and impact events
  • Explore the LPSC (Lunar and Planetary Science Conference) extended abstracts for relevant studies
  • Investigate the Scientific American article on Martian ejecta for detailed insights
  • Study the dynamics of meteoritic material from the Kuiper Belt and its implications for planetary geology
USEFUL FOR

Astronomers, planetary scientists, and researchers interested in meteoritics and planetary geology will benefit from this discussion, particularly those analyzing the transfer of material between celestial bodies.

swampwiz
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I was reading this (which is notable for its non-science content, but I am only referring to this part):
https://www.nationalreview.com/2020/11/wokeists-assault-space-exploration
... it is estimated that every year, approximately 500 kilograms of rocks ejected from Mars via meteoric impact land on our planet.
Is there a matrix that shows the amount that goes between the planets? (And here, I consider a moon to be a "planet".)
 
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No one has any idea?
 
It is not that simple. Try this search on google scholar 'estimates of planetary ejecta hitting earth'

Lots of good hits. You need to decide your parameters, the diversity of topics is not small.
 
swampwiz said:
I was reading this (which is notable for its non-science content, but I am only referring to this part):
https://www.nationalreview.com/2020/11/wokeists-assault-space-exploration

Is there a matrix that shows the amount that goes between the planets? (And here, I consider a moon to be a "planet".)
I would like to see references for their claims for the "billions of tons" and the 500kg/yr
They both seem extreme.
 
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Let’s assume 10^9 metric tons. Surface density of 2000kg/m^3. That gives a 793m cube removed per year. That seems big, but not obscenely big. It could even be right. One is integrating over a lot of impacts.

I would also check out LPSC extended abstracts.
 
caz said:
Let’s assume 10^9 metric tons. Surface density of 2000kg/m^3. That gives a 793m cube removed per year. That seems big, but not obscenely big. It could even be right. One is integrating over a lot of impacts.

I would also check out LPSC extended abstracts.
I could believe the figures for ALL meteorites, but just for Martian material, a bit hard to swallow

The rate for ALL meteoritic material is an avg of 50,000 tonnes / year
Wiki at ~ 15,000 tonnes / yr is very low compared to other sites
 
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davenn said:
I would like to see references for their claims for the "billions of tons" and the 500kg/yr
They both seem extreme.

The numbers all seem to be huge but intuition can be very misleading.
The mechanism for ejection from a planet has to be a collision as some other mass comes in and collides with the surface. I would imagine there would have to be unusual circumstances for this to happen as most of the Kinetic Energy of the incident mass would be shared.

If the incident mass were to arrive from the Kuiper belt, say, it could have enough energy to eject a similar size mass into a much lower orbit - to collide with another inner (rocky) planet. But you would think that there would be far fewer rocks ejected than arriving. These events would all be pretty newsworthy on Earth but probably no one would be aware of an ejection event.

Having a rarified atmosphere and moderate gravity, Mars would perhaps be a better candidate for supplying rocks to Earth than the other way round. The Moon, even better.
 

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