<p>I think you're overestimating the danger here.</p>
<p>The Asteroid Watch tool currently shows five near-earth astroids that are going to pass close (relatively speaking) in the next several days.</p>
<p>The nearest approach of all of them will be 2024 JV8, estimated at 20.2 meters across, passing about 1.5x moon-distances from us.</p>
<p>So first I think you need to really think about how far the moon is. In terms of the solar system, yeah, it's right next door, but it's also 363,000 km away. The whole planet is only 12,700 km wide -- the earth-moon system is mostly empty space. &quot;Half again as far as the moon&quot; is a huge margin to miss the planet by. Is it worth watching? Sure. But is it indicative of a present danger? Nah.</p>
<p>Second, that asteroid is only 20 meters wide. It's basically a Chelyabinsk. If it did hit the planet, we would expect it to break up in the high atmosphere and, at worst, break some windows with the bang (but it's vastly more likely it would come in over the ocean and no human being would even see it). We get one of those a couple times a century. Notable, but not particularly dangerous. Thunderstorms are orders of magnitude more hazardous to human life.</p>
<p>The largest of the bunch is 2024 MT1, at 82 meters. If it hit the planet, that would be a local disaster and an event of worldwide interest, like a large volcano or earthquake. It could cause mass casualties if it happened near a populated area (again, like a volcano or earthquake). We estimate that a meteor like that hits the planet about once every ten thousand years, or in other words about once in a metric Human Civilization.</p>
<p>But its closest approach is about 4 times the distance to the moon. And I think it's important to remember that the target the object has to pass through to be &quot;four times the distance to the moon&quot; is absolutely enormous. It's not 4 times bigger than a circle the size of the moon's orbit; it's 16 times bigger. And the moon itself is ~30 earth diameters away, so if the moon's orbit outlines a dartboard, the bullseye that is Earth is only 1/900th of the dartboard.</p>
<p>Again, is it worth noticing? Sure. And we're tracking things like that now. But it's not a cause for alarm.</p>
<p>We can look at human history and estimate how alarming any of this should be. How many meteor strikes have wiped out cities in all of our known past? How often does an asteroid impact cause planetary mass extinction? How often do we even have a new crater to go look at? Past performance is no guarantee of future results, but just by looking at our known history, we can estimate how much of a threat any of this is, and quite frankly a rock from the sky hardly even makes the list compared to our usual supply of natural and man-made disasters.</p>

CC BY-SA 4.0
2024-07-04T03:36:16.277Z
Wow great answer. "We can look at human history and estimate how alarming any of this should be. How many meteor strikes have wiped out cities" == yes, that's what keeps me from panicking. Then I think of tiscunga, cherblyinsk, and how many over the oceans -- all in one human lifetime. Of a really old person.
Miss Understands
CC BY-SA 4.0
2024-07-04T11:46:30.933Z
It's the cross-sectional area that matters not the volume. I.E. probability of getting within $r$ goes as $r^2$. The lifetime risk of being killed by an asteroid is higher than an airplane crash for most people I believe.
ProfRob
CC BY-SA 4.0
2024-07-05T00:44:37.657Z
@Miss_Understands Right, but Chelyabinsk didn't cause any fatalities, let alone wipe out a city. Tunguska, the biggest impact event in recorded history, *may* have killed three nomadic herders. Like sure, if that hit a city, it would be like dropping an H-bomb on the place, but the amount of Earth's surface covered in city is minuscule, less than 1% of the surface area. Could it happen? Sure. But it's not worth worrying about.
Darth Pseudonym
CC BY-SA 4.0
2024-07-05T00:50:35.143Z
@ProfRob Yeah, fair enough.  Updated.
Darth Pseudonym
CC BY-SA 4.0
2024-07-09T21:09:22.560Z
Thank you for introducing me to the "metric Human Civilization" unit of measurement
Yorik
CC BY-SA 4.0
2024-07-04T02:50:09.370Z
2024-07-05T00:50:08.227Z
2024-07-05T00:50:08.227Z
Darth Pseudonym
<p>Here in The Future, we have a Planetary Defense Force. And they have a <a href="https://eyes.nasa.gov/apps/asteroids/#/home" rel="nofollow noreferrer">3D asteroid simulator</a> that shows thousands of dangerous rocks moving in 3D real time.</p>
<p>Somehow, on the graphics screen, you can get it to show the next 5 asteroid close calls.</p>
<ul>
<li><p>They are all <em>this week!</em></p>
</li>
<li><p>Some were 100 meters long!</p>
</li>
<li><p>Some were real close. (Data was not copy-pastable).</p>
</li>
</ul>
<p>That's outrageous! We get a Tunguska once a century, but another one barely misses us <em>every day?</em></p>
<p>Does a football field size asteroid really fall past the moon once a week? Or is this just a bad week?</p>

CC BY-SA 4.0
2024-07-03T14:21:46.213Z
Can you take screenshots or something to get the specific information you're talking about? Looking at the Asteroid Watch tool on that page, none of the next 5 "close" approaches are nearer than half a million km, nor are any of them even close to 100 meters. The largest one I see listed is "2024 MT1" at about 83 meters wide, and it won't come closer than 1.5 million km, or ~4 times the distance to the moon.
Darth Pseudonym
CC BY-SA 4.0
2024-07-03T18:38:29.287Z
Seems like the answer is No based on spaceweather.com. Asteroids passing by? Plenty. Larger than 100 m? Few. Closer than the Moon? Even fewer. A miss is a miss, doesn't matter about the size or distance when comparing to Tunguska.
JohnHoltz
CC BY-SA 4.0
2024-07-04T00:10:59.713Z
@DarthPseudonym 83 meters is nearly 100, and equally alarming. one of the 5 is moon distance. and one of them comes in slightly more than a week, not 1 week as I said. Also note that 2 days have passed so they're different now. MY POINT IS that I didn't know this rain of death was happening and we're blissfully unaware except when one of them levels a forest or  blows out all the windows in a city. My question was to confirm this latest horror in life.  I was asking, do I have this correct, is this really happening? I guess it is. Okay.  Rain of death. Oh well.
Miss Understands
<asteroids>
Does a football field size asteroid really fall past the moon once a week?
Miss Understands
# Does a football field size asteroid really fall past the moon once a week?

(Asked by: username_0 on 2024-07-03)

Here in The Future, we have a Planetary Defense Force. And they have a [3D asteroid simulator](https://eyes.nasa.gov/apps/asteroids/#/home) that shows thousands of dangerous rocks moving in 3D real time.

Somehow, on the graphics screen, you can get it to show the next 5 asteroid close calls.

* They are all *this week!*
* Some were 100 meters long!
* Some were real close. (Data was not copy-pastable).

That's outrageous! We get a Tunguska once a century, but another one barely misses us *every day?*

Does a football field size asteroid really fall past the moon once a week? Or is this just a bad week?

**Tags:** asteroids

> **Comments:**
> **username_1**: Can you take screenshots or something to get the specific information you're talking about? Looking at the Asteroid Watch tool on that page, none of the next 5 "close" approaches are nearer than half a million km, nor are any of them even close to 100 meters. The largest one I see listed is "2024 MT1" at about 83 meters wide, and it won't come closer than 1.5 million km, or ~4 times the distance to the moon.  
> **username_2**: Seems like the answer is No based on spaceweather.com. Asteroids passing by? Plenty. Larger than 100 m? Few. Closer than the Moon? Even fewer. A username_0 is a username_0, doesn't matter about the size or distance when comparing to Tunguska.  
> **username_0**: @username_1 83 meters is nearly 100, and equally alarming. one of the 5 is moon distance. and one of them comes in slightly more than a week, not 1 week as I said. Also note that 2 days have passed so they're different now. MY POINT IS that I didn't know this rain of death was happening and we're blissfully unaware except when one of them levels a forest or  blows out all the windows in a city. My question was to confirm this latest horror in life.  I was asking, do I have this correct, is this really happening? I guess it is. Okay.  Rain of death. Oh well.  

---

## 1 answers

### Answer by username_1 on 2024-07-04. Score: 4 | Accepted answer

I think you're overestimating the danger here.

The Asteroid Watch tool currently shows five near-earth astroids that are going to pass close (relatively speaking) in the next several days.

The nearest approach of all of them will be 2024 JV8, estimated at 20.2 meters across, passing about 1.5x moon-distances from us.

So first I think you need to really think about how far the moon is. In terms of the solar system, yeah, it's right next door, but it's also 363,000 km away. The whole planet is only 12,700 km wide -- the earth-moon system is mostly empty space. "Half again as far as the moon" is a huge margin to username_0 the planet by. Is it worth watching? Sure. But is it indicative of a present danger? Nah.

Second, that asteroid is only 20 meters wide. It's basically a Chelyabinsk. If it did hit the planet, we would expect it to break up in the high atmosphere and, at worst, break some windows with the bang (but it's vastly more likely it would come in over the ocean and no human being would even see it). We get one of those a couple times a century. Notable, but not particularly dangerous. Thunderstorms are orders of magnitude more hazardous to human life.

The largest of the bunch is 2024 MT1, at 82 meters. If it hit the planet, that would be a local disaster and an event of worldwide interest, like a large volcano or earthquake. It could cause mass casualties if it happened near a populated area (again, like a volcano or earthquake). We estimate that a meteor like that hits the planet about once every ten thousand years, or in other words about once in a metric Human Civilization.

But its closest approach is about 4 times the distance to the moon. And I think it's important to remember that the target the object has to pass through to be "four times the distance to the moon" is absolutely enormous. It's not 4 times bigger than a circle the size of the moon's orbit; it's 16 times bigger. And the moon itself is ~30 earth diameters away, so if the moon's orbit outlines a dartboard, the bullseye that is Earth is only 1/900th of the dartboard.

Again, is it worth noticing? Sure. And we're tracking things like that now. But it's not a cause for alarm.

We can look at human history and estimate how alarming any of this should be. How many meteor strikes have wiped out cities in all of our known past? How often does an asteroid impact cause planetary mass extinction? How often do we even have a new crater to go look at? Past performance is no guarantee of future results, but just by looking at our known history, we can estimate how much of a threat any of this is, and quite frankly a rock from the sky hardly even makes the list compared to our usual supply of natural and man-made disasters.

> **Comments:**
> **username_0**: Wow great answer. "We can look at human history and estimate how alarming any of this should be. How many meteor strikes have wiped out cities" == yes, that's what keeps me from panicking. Then I think of tiscunga, cherblyinsk, and how many over the oceans -- all in one human lifetime. Of a really old person.  
> **username_3**: It's the cross-sectional area that matters not the volume. I.E. probability of getting within $r$ goes as $r^2$. The lifetime risk of being killed by an asteroid is higher than an airplane crash for most people I believe.  
> **username_1**: @username_0 Right, but Chelyabinsk didn't cause any fatalities, let alone wipe out a city. Tunguska, the biggest impact event in recorded history, *may* have killed three nomadic herders. Like sure, if that hit a city, it would be like dropping an H-bomb on the place, but the amount of Earth's surface covered in city is minuscule, less than 1% of the surface area. Could it happen? Sure. But it's not worth worrying about.  
> **username_1**: @username_3 Yeah, fair enough.  Updated.  
> **username_4**: Thank you for introducing me to the "metric Human Civilization" unit of measurement  

---

