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Impact: Earth! A meteor/comet impact simulator

  1. Mar 1, 2015 #1


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    Impact: Earth!

    A meteor/comet impact simulator(text only) provided by Purdue University.

    Lots of fun. :smile:

    You can smash things into the Earth varying the diameter, density, velocity, angle, land or water entry, and your distance from impact.

    1 meter: very boring. happens every 1.1 year. Even if you are within 1 km, they claim you can't hear it.
    950 km(Ceres!): also kind of boring, but I had the speed set at minimum. Though at 1000 km, you'll be hit by 50,000 mph winds, and be covered by 36 miles of "ejecta".

    The middling things are more interesting.
    And you can chose from a list.

    Apophis!: 260 meters
    My settings: 72 m/s, 90° entry, impacting sedimentary rock
    At 10km from impact:
    Max wind velocity: 1430 m/s = 3200 mph
    Duration of Irradiation: 1.39 minutes
    Radiant flux (relative to the sun): 1880
    Sound Intensity: 130 dB (Dangerously Loud)​

    Ha! Dangerously loud, so cover your ears, before you're hit by 3200 mph winds, and burst spontaneously into flames. Ha!

    Anyways, it's something to play with, if you're bored.

    ps. This came across on Facebook today. There was a related video apparently put together by the Discovery Channel, that lasts about 5 minutes.
    It's a simulation of a 500 km asteroid striking somewhere in the Pacific ocean.
    The music is very nice: The Great Gig In The Sky, from Dark Side of the Moon.
  2. jcsd
  3. Mar 2, 2015 #2
    oh boy this is devilishly fun! Anyone will some interesting numbers?
  4. Mar 2, 2015 #3


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    If you skip the moon like a rock on a pond, at zero degrees, nothing happens. (any speed)
    If you change the angle of entry to 1°, all hell breaks loose: Richter Scale Magnitude: 14.6 (This is greater than any earthquake in recorded history)
    At 90° and full speed: 100 percent of the Earth is melted.

    And FYI, the average depth of the Pacific is about 4300 meters. Tsunamis are fun too. But the asteroids have to be pretty big. A 10 meter iron asteroid disintegrates between 1/2 and 10 miles above the surface of the earth, depending on it's initial velocity.

    100 meter asteroids make good tsunamis.
    150 - 300 ft high. (minimum entry speed)
    740 - 1480 ft high (maximum entry speed)​
  5. Mar 2, 2015 #4
    It's more scary than fun. Especially the video :eek:
  6. Mar 2, 2015 #5


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    The video is mostly Hollywood.
    According to "Impact: Earth!", regarding an asteroid of that size:

    The average interval between impacts of this size is longer than the Earth's age.
    Such impacts could only occur during the accumulation of the Earth, between 4.5 and 4 billion years ago.

    I think this will be a useful tool, for the future, when the media gets all woo-wooey with doom and gloom, and their scary numbers.

    For instance:

    Now we have a tool to plug the numbers into, and can see what happens.

    The average interval between impacts of this size somewhere on Earth is 523 years

    Final Crater Diameter: 1.05 km ( = 0.651 miles )
    Final Crater Depth: 223 meters ( = 732 feet )

    Quite impressive crater!
    If it were to impact the heart of my city, it would kill tens of thousands.
    But I live 8 km away, and would feel only a minor earthquake (4.7).
    And the air blast is still quite impressive at such a distance:
    Max wind velocity: 33.7 m/s = 75.4 mph
    Sound Intensity: 84 dB (Loud as heavy traffic)
    Damage Description:
    Glass windows will shatter.

    But diddling with the numbers, you can see that most of my friends would probably die!
    2 km from the epicenter:
    Peak Overpressure: 211000 Pa = 2.11 bars = 30 psi
    Max wind velocity: 297 m/s = 665 mph
    [= dead, imho]​
    3 km:
    Max wind velocity: 162 m/s = 362 mph [= probably dead]​

    But, in the bigger scheme of things, based on PF's x-axis picture limit, the crater would be as big as a single pixel in the below image.

    New game. Find the crater!

  7. Jun 20, 2015 #6
    Any idea how to make a really deep crater? At best while leaving most of the planet more or less intact.

    (Even if I crash 300 km of iron at 72 km/s, almost perpendicular, I get underwhelming 4.3 km deep crater)
  8. Jun 20, 2015 #7


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    ya nic nie wiem.

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