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Does the moon take a lot of impacts that would have been destined for earth?

by GEBBL 4y ago

MonkeyClub 4y ago
I have the same question, if anyone knows the answer it'd be awesome. I mean, sure, simply by virtue of the moon's being there, it sort of fends some stuff off like a fence. But beyond that, is its gravitational pull adequate to affect trajectories? If so, wouldn't earth's trump it? (Although the inverse square here may play a big part, but that would also make me more inclined to disregard the moon's gravity pull as assisting in any protection it otherwise naturally affords.) Edit: clarified (?) thought
- thehappypm 4y ago
  It’s really more that the moon has no atmosphere. A shooting star on Earth would be a crater on the moon.
  - krapp 4y ago
    Ackshually, the moon has a very thin atmosphere, primarily composed of neon, helium and hydrogen.
    - outworlder 4y ago
      Not enough to matter for most purposes.
- h2odragon 4y ago
  I think the effect of the moon is not so much "catching" things as it is perturbing orbits near earth such that things either crash into earth or moon or get flung away. Without the moon we might have a lot more stuff in solar orbits that overlap earths orbit. I expect this could be explained better (and I may well be totally wrong).
- mannykannot 4y ago
  The first requirement for a piece of space junk to hit the moon is to be on an orbit that will cross the moon's. Most space junk is left over from launching things into earth orbit (geostationary or lower), and so will not be going fast enough.
jstanley 4y ago
Most of the stuff that leaves a small crater on the moon would burn up in Earth's atmosphere long before it hits the ground.
iamgopal 4y ago
That would be Jupiter and Saturn. For this instance, it’s other way around.
- gambiting 4y ago
  Yeah, Jupiter is basically a giant hoover of the solar system - apparently without it Earth would be constantly getting hit by outer space junk.
tiffanyh 4y ago
Random Factoid: it's extremely rare but the reason why the moon appears the same size as the sun is that the sun is 400x wider than the moon, but also 400x farther from the earth than the moon is. Our moon holds so many mysteries. Just the very fact that such a large object can be so close in proximity to us while also orbiting is mind boggling. https://astronomy.com/magazine/ask-astro/2000/10/why-is-the-moon-exactly-the-same-apparent-size-from-earth-as-the-sun-surely-this-cannot-be-just-coincidence-the-odds-against-such-a-perfect-match-are-enormous https://astronomy.com/magazine/ask-astro/2000/10/why-is-the-...
- closewith 4y ago
  That seems to be actually be true, not a factoid?
  - vlovich123 4y ago
    American heritage dictionary: factoid făk′toid noun 1. A piece of unverified or inaccurate information that is presented in the press as factual, often as part of a publicity effort, and that is then accepted as true because of frequent repetition. 2. A brief, somewhat interesting fact. 3. An inaccurate statement or statistic believed to be true because of broad repetition, especially if cited in the media. I assume the definition used here is #2. I’m actually surprised by 1 and 3. I have never heard it used in that context and it’s strange that one word would have 2 fairly contradictory interpretations.
    - closewith 4y ago
      That is interesting! I've never come across the second definition before. Wikipedia suggests that usage become common following CNN misusing the original Norman Mailer meaning during broadcasts in the eighties. https://en.wikipedia.org/wiki/Factoid https://en.wikipedia.org/wiki/Factoid
      - athorax 4y ago
        Now that is an interesting factoid!
BurningFrog 4y ago
About as much as the percentage of the sky it covers, I assume?
- vikingerik 4y ago
  This is correct, and it's not much, the Moon covers only 1/210000th of Earth's sky. https://en.wikipedia.org/wiki/Square_degree https://en.wikipedia.org/wiki/Square_degree The Moon does take slightly more than that proportion of impacts that would hit Earth, because the distribution of approach vectors of impacting bodies isn't uniform, but clusters around the ecliptic plane, and so does the Moon's orbit. But it's still a small number.

Does the moon take a lot of impacts that would have been destined for earth?

by GEBBL 4y ago

Does the moon take a lot of impacts that would have been destined for earth?

I have the same question, if anyone knows the answer it'd be awesome. I mean, sure, simply by virtue of the moon's being there, it sort of fends some stuff off like a fence. But beyond that, is its gravitational pull adequate to affect trajectories? If so, wouldn't earth's trump it? (Although the inverse square here may play a big part, but that would also make me more inclined to disregard the moon's gravity pull as assisting in any protection it otherwise naturally affords.) Edit: clarified (?) thought

thehappypm 4y ago
It’s really more that the moon has no atmosphere. A shooting star on Earth would be a crater on the moon.
- krapp 4y ago
  Ackshually, the moon has a very thin atmosphere, primarily composed of neon, helium and hydrogen.
  - outworlder 4y ago
    Not enough to matter for most purposes.
h2odragon 4y ago
I think the effect of the moon is not so much "catching" things as it is perturbing orbits near earth such that things either crash into earth or moon or get flung away. Without the moon we might have a lot more stuff in solar orbits that overlap earths orbit. I expect this could be explained better (and I may well be totally wrong).
mannykannot 4y ago
The first requirement for a piece of space junk to hit the moon is to be on an orbit that will cross the moon's. Most space junk is left over from launching things into earth orbit (geostationary or lower), and so will not be going fast enough.

jstanley 4y ago

Most of the stuff that leaves a small crater on the moon would burn up in Earth's atmosphere long before it hits the ground.

iamgopal 4y ago

That would be Jupiter and Saturn. For this instance, it’s other way around.

gambiting 4y ago
Yeah, Jupiter is basically a giant hoover of the solar system - apparently without it Earth would be constantly getting hit by outer space junk.

tiffanyh 4y ago

Random Factoid: it's extremely rare but the reason why the moon appears the same size as the sun is that the sun is 400x wider than the moon, but also 400x farther from the earth than the moon is. Our moon holds so many mysteries. Just the very fact that such a large object can be so close in proximity to us while also orbiting is mind boggling. https://astronomy.com/magazine/ask-astro/2000/10/why-is-the-moon-exactly-the-same-apparent-size-from-earth-as-the-sun-surely-this-cannot-be-just-coincidence-the-odds-against-such-a-perfect-match-are-enormous https://astronomy.com/magazine/ask-astro/2000/10/why-is-the-...

closewith 4y ago
That seems to be actually be true, not a factoid?
- vlovich123 4y ago
  American heritage dictionary: factoid făk′toid noun 1. A piece of unverified or inaccurate information that is presented in the press as factual, often as part of a publicity effort, and that is then accepted as true because of frequent repetition. 2. A brief, somewhat interesting fact. 3. An inaccurate statement or statistic believed to be true because of broad repetition, especially if cited in the media. I assume the definition used here is #2. I’m actually surprised by 1 and 3. I have never heard it used in that context and it’s strange that one word would have 2 fairly contradictory interpretations.
  - closewith 4y ago
    That is interesting! I've never come across the second definition before. Wikipedia suggests that usage become common following CNN misusing the original Norman Mailer meaning during broadcasts in the eighties. https://en.wikipedia.org/wiki/Factoid https://en.wikipedia.org/wiki/Factoid
    - athorax 4y ago
      Now that is an interesting factoid!

BurningFrog 4y ago

About as much as the percentage of the sky it covers, I assume?

vikingerik 4y ago
This is correct, and it's not much, the Moon covers only 1/210000th of Earth's sky. https://en.wikipedia.org/wiki/Square_degree https://en.wikipedia.org/wiki/Square_degree The Moon does take slightly more than that proportion of impacts that would hit Earth, because the distribution of approach vectors of impacting bodies isn't uniform, but clusters around the ecliptic plane, and so does the Moon's orbit. But it's still a small number.