
Every recorded meteorite strike on Earth since 2,300 BCE mapped - blazingfrog2
http://osm2.cartodb.com/tables/2320/public#/map
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NelsonMinar
This map is a great example of how Google Mercator is not always the right
projection for a visualization. Antarctica is an important source for
meteorite research; black specs are easy to pick off the white ice. But this
map projection completely distorts Antarctica so you can't really read that
part of the data. Cool map, but sometimes the off-the-shelf map tool isn't the
right choice.

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a235
It's not google. This one is based on <http://cartodb.com/>, however the
argument is still valid

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sp332
This reply from Google explains why they use Mercator.
[http://productforums.google.com/d/msg/maps/A2ygEJ5eG-o/KbZr_...](http://productforums.google.com/d/msg/maps/A2ygEJ5eG-o/KbZr_B0h2hkJ)
Not sure if it's really satisfactory, but at least there's a reason.

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ggchappell
Nice.

Some kind of explanation would be helpful, though. Apparently the size of the
circle is related to the mass of the meteorite, and color is density of
circles. But it took me a while to figure that out.

Also, what happened in Oman?

EDIT: Wikipedia says, "The central desert of Oman is an important source of
meteorites for scientific analysis." Possibly meteorites are just easier to
find there, due to properties of the terrain. Perhaps meteorite hunting is a
popular sport/business, too?

~~~
tarekayna
Apparently Oman is a destination for meteorite explorers. That explains the
difference between Oman and Saudi Arabia on the map.
[http://www.livescience.com/3613-searching-meteorites-
deserts...](http://www.livescience.com/3613-searching-meteorites-deserts-
oman.html)

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benhamner
More accurately described as "where people were located since 2,300 BCE that
were capable of recording meteor strikes and recorded them in a form that
survived until present day and made its way into a database of meteor
strikes." Latitudinal variations in the density of meteor strikes wouldn't
surprise me; longitudinal ones should be entirely explained by the
observational effect. Hence we see a ton of meteor strikes in the continental
US and virtually none in rural China, though both are on similar latitudes.

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ra
What's the data source? If it's the US meteorical society database, then it
probably includes "finds" in additional to witnessed "falls".

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jlgreco
Interesting. The relatively high number in India compared to surrounding
locations says to me that there is a strong component of culture (determines
if things are recorded) and population density. On the other hand, flyover
country in the US seems to get more than the coasts, despite population
density, so perhaps light pollution on the coasts is skewing the results?

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a235
sorry, but this is another population density map

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Turing_Machine
Not really.

Note the large number of strikes in the Sahara desert (and Antarctica, as
someone else noted).

There are _at least_ two things going on here, probably more:

1) Population density 2) Ease of finding the meteorite or crater (this is
easier in barren areas with relatively homogeneous terrain, like the desert
and Antartica).

~~~
a235
You right, but I still see this map as a catalogue of found meteors, rather
than an informative visualisation. To make your observations clear, you need
to normalise this heatmap by the population density.

~~~
Turing_Machine
It depends on what you're after. What you're suggesting would would also
distort the data, but in a different way -- it'd make it look like Antarctica
was far more likely to get hit than it actually is.

One would expect the true distribution to be extremely uniform, right?

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ryusage
Overall, yes. I wonder, though, could the spin of the Earth have any effect on
the distribution?

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kaybe
Improbable.

However, there could be a favoured plane of arrival, like the solar system
plane, and with a circular cross section of the Earth I'd expect less
debris/area near the poles. (I don't _know_ this, I'm just extrapolating from
what I actually know.)

~~~
lutusp
> ... with a circular cross section of the Earth I'd expect less debris/area
> near the poles.

As it turns out, Antarctica is a very productive place to look for meteorites,
first because there isn't really a preferred geographical zone for meteorite
impacts, and second because of the large, empty ice fields, against which
newly fallen meteorites stand out.

One of the most famous meteorite finds of all time, ALH84001, was located by
simply driving across the Antarctica landscape and watching for dark objects.

<http://en.wikipedia.org/wiki/Allan_Hills_84001>

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ars
Are the patterns I see here artifacts of the data collection method, or do
meteors really prefer the northern hemisphere?

~~~
gilgoomesh
Almost exclusively due to the data collection method. Specifically, only
_recorded_ strikes are shown -- someone had to find the meteorite and publish
its existence. Hence the dense jungles of Congo are relatively empty compared
to the well trodden plains of Kenya.

Also notice: the only plotted strikes in Antarctica are right near the
scientific stations -- but the intensity is _very_ high at those points.

If you plotted theoretical meteorite distributions, there would be more
strikes at the poles than the equator (due to the Earth's rotation, the poles
receive many more meteorites) but at a given latitude the distribution would
be even.

~~~
wtvanhest
_Also notice: the only plotted strikes in Antarctica are right near the
scientific stations -- but the intensity is very high at those points.

If you plotted theoretical meteorite distributions, there would be more
strikes at the poles than the equator (due to the Earth's rotation, the poles
receive many more meteorites) but at a given latitude the distribution would
be even._

Could someone who understands this really well explain why the rotation of
earth would change the number of meteorite strikes near the equator?

(It seems to me that strikes should be completely randomly distributed across
the earth's surface and if a meteorite was headed for one area of the equator
and the earth was spinning, the meteorite would simply hit another area of the
equator.) I'm probably missing something here, but I can't figure out what.

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subway
I wonder what data source was used. I've confirmed a few strikes several miles
from where they actually hit. (A Kendall County, TX strike appeared south of
San Antonio, and a Louisville, KY strike appeared downtown while the actual
strike occurred several miles from downtown.

~~~
ryusage
The table gives a source for every data item. They all look to be from here:
<http://www.lpi.usra.edu/meteor/metbull.php>

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damon_c
Some of these comments raised a lot of questions about meteor distribution due
to orbital/rotational effects.

Found some answers here:
<http://curious.astro.cornell.edu/question.php?number=746>

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JoeAltmaier
Logically oceans get hit at the same rate. Also land that is now under water.
Are there any recorded oceanic meteor strikes in this map?

Oh! The one that killed the dinosaurs. It was pretty big. Maybe only the big
ones leave a mark on the ocean floor.

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jatorre
Some explanation over the map is here
[http://www.theverge.com/2013/2/18/4001936/map-every-
recorded...](http://www.theverge.com/2013/2/18/4001936/map-every-recorded-
meteorite-strike-earth-2300-BCE)

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menacingly
They seem to concentrate in areas with the means to record them

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vincefutr23
it would be interesting to overlay geography and population maps on top of
this data. It seems as if the most density comes in areas with flat,
unobstructed land, but also with relatively high populations. Assuming random
strikes, mere desserts or population centers do not seem enough to generate
density, it must be a combination of prairie/desert and people such as Kansas
or Northern Texas

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jatorre
If you are interested on how it was made, checkout
<https://vimeo.com/59791629>

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jmadsen
Interesting - there is a perception, I think, that Russia gets hit by more
than their share, but actually opposite seems true

