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Distance from Impact: 500.00 km ( = 311.00 miles )
Projectile diameter: 400.00 meters ( = 1310.00 feet )
Projectile Density: 3000 kg/m3
Impact Velocity: 25.00 km per second ( = 15.50 miles per second )
Impact Angle: 20 degrees
Target Density: 1000 kg/m3
Target Type: Liquid water of depth 2.0 km ( = 1.2 miles ), over crystalline rock.
Energy:
Energy before atmospheric entry: 3.14 x 1019 Joules = 7.50 x 103 MegaTons TNT
The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 1.1 x 105years
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).
The impact does not shift the Earth's orbit noticeably.
Atmospheric Entry:
The projectile begins to breakup at an altitude of 60200 meters = 198000 ft
The projectile reaches the ground in a broken condition. The mass of projectile strikes the surface at velocity 21.4 km/s = 13.3 miles/s
The impact energy is 2.31 x 1019 Joules = 5.51 x 103MegaTons.
The broken projectile fragments strike the ground in an ellipse of dimension 3.64 km by 1.25 km
Crater Dimensions:
The crater opened in the water has a diameter of 7.18 km ( = 4.46 miles ).
For the crater formed in the seafloor:
The result of the impact is a crater field, not a single crater. The following dimensions are for the crater produced by the largest fragment.
Transient Crater Diameter: 131 meters ( = 428 feet )
Transient Crater Depth: 46.2 meters ( = 151 feet )
Final Crater Diameter: 163 meters ( = 536 feet )
Final Crater Depth: 34.8 meters ( = 114 feet )
The crater formed is a simple crater
The floor of the crater is underlain by a lens of broken rock debris (breccia) with a maximum thickness of 16.1 meters ( = 52.8 feet ).
The volume of the target melted or vaporized is 190 m3 = 6700 feet3
Roughly half the melt remains in the crater.
Seismic Effects:
The major seismic shaking will arrive approximately 1.67 minutes after impact.
Richter Scale Magnitude: 3.4
Mercalli Scale Intensity at a distance of 500 km:
Nothing would be felt. However, seismic equipment may still detect the shaking.
Air Blast:
The air blast will arrive approximately 25.3 minutes after impact.
Peak Overpressure: 2220 Pa = 0.0222 bars = 0.315 psi
Max wind velocity: 5.18 m/s = 11.6 mph
Sound Intensity: 67 dB (Loud as heavy traffic)
Tsunami Wave:
The impact-generated tsunami wave arrives approximately 1.1 hours after impact.
Tsunami wave amplitude is less than 7.2 meters ( = 23.6 feet).
Earth Impact Effects Program