Please note: the results below are estimates based on current (limited) understanding of the impact process and come with large uncertainties; they should be used with caution, particularly in the case of peculiar input parameters. All values are given to three significant figures but this does not reflect the precision of the estimate. For more information about the uncertainty associated with our calculations and a full discussion of this program, please refer to this article
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Your Inputs:
- Distance from Impact: 4000.00 km ( = 2480.00 miles )
- Projectile diameter: 25.00 km ( = 15.50 miles )
- Projectile Density: 1500 kg/m3
- Impact Velocity: 57.00 km per second ( = 35.40 miles per second )
- Impact Angle: 40 degrees
- Target Density: 2500 kg/m3
- Target Type: Sedimentary Rock
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Energy:
- Energy before atmospheric entry: 1.99 x 1025 Joules = 4.76 x 109 MegaTons TNT
- The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 3.1 x 109years
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Major Global Changes:
- The Earth is not strongly disturbed by the impact and loses negligible mass.
- The impact does not make a noticeable change in the tilt of Earth's axis (< 5 hundreths of a degree).
- Depending on the direction and location of impact, the collision may cause a change in the length of the day of up to 41.8 milliseconds.
- The impact does not shift the Earth's orbit noticeably.
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Crater Dimensions:
- What does this mean?
- Transient Crater Diameter:
171 km ( = 106 miles )
- Transient Crater Depth: 60.3 km ( = 37.4 miles )
- Final Crater Diameter:
335 km ( = 208 miles )
- Final Crater Depth: 1.7 km ( = 1.06 miles )
- The crater formed is a complex crater.
- The volume of the target melted or vaporized is 114000 km3 = 27300 miles3
- Roughly half the melt remains in the crater, where its average thickness is 4.99 km ( = 3.1 miles ).
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Thermal Radiation:
- What does this mean?
- The fireball is below the horizon. There is no direct thermal radiation.
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Seismic Effects:
- What does this mean?
The major seismic shaking will arrive approximately 13.3 minutes after impact.- Richter Scale Magnitude: 11.1 (This is greater than any earthquake in recorded history)
- Mercalli Scale Intensity at a distance of 4000 km:
IV. Felt indoors by many, outdoors by few during the day. At night, some awakened. Dishes, windows, doors disturbed; walls make cracking sound. Sensation like heavy truck striking building. Standing motor cars rocked noticeably.
V. Felt by nearly everyone; many awakened. Some dishes, windows broken. Unstable objects overturned. Pendulum clocks may stop.
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Ejecta:
- What does this mean?
The ejecta will arrive approximately 21.5 minutes after the impact.- At your position there is a fine dusting of ejecta with occasional larger fragments
- Average Ejecta Thickness: 11.8 cm ( = 4.65 inches )
- Mean Fragment Diameter: 133 microns ( = 5.25 thousandths of an inch )
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Air Blast:
- What does this mean?
The air blast will arrive approximately 3.37 hours after impact.- Peak Overpressure: 112000 Pa = 1.12 bars = 15.9 psi
- Max wind velocity: 188 m/s = 421 mph
- Sound Intensity: 101 dB (May cause ear pain)
- Damage Description:
Multistory wall-bearing buildings will collapse.
Wood frame buildings will almost completely collapse.
Highway truss bridges will suffer substantial distortion of bracing.
Glass windows will shatter.
Up to 90 percent of trees blown down; remainder stripped of branches and leaves.
Tell me more...
Click here for a pdf document that details the observations, assumptions, and equations upon which this program is based. It
describes our approach to quantifying the important impact processes that might affect the people, buildings, and landscape in the
vicinity of an impact event and discusses the uncertainty in our predictions. The processes included are: atmospheric entry, impact
crater formation, fireball expansion and thermal radiation, ejecta deposition, seismic shaking, and the propagation of the atmospheric
blast wave.
Recent improvements in the airblast calculation are described here.
Earth Impact Effects Program Copyright 2004, Robert Marcus, H.J. Melosh, and G.S. Collins
These results come with ABSOLUTELY NO WARRANTY