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
- Distance from Impact: 200.00 km ( = 124.00 miles )
- Projectile diameter: 1000.00 meters ( = 3280.00 feet )
- Projectile Density: 500 kg/m3
- Impact Velocity: 300.00 km per second ( = 186.00 miles per second )
(Your chosen velocity is higher than the maximum for an object orbiting the sun)
- Impact Angle: 5 degrees
- Target Density: 2750 kg/m3
- Target Type: Crystalline Rock
- Energy before atmospheric entry: 1.18 x 1022 Joules = 2.81 x 106 MegaTons TNT
- The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 1.0 x 107years
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.
- The projectile begins to breakup at an altitude of 137000 meters = 450000 ft
- The projectile bursts into a cloud of fragments at an altitude of 8260 meters = 27100 ft
- The residual velocity of the projectile fragments after the burst is 25.8 km/s = 16 miles/s
- The energy of the airburst is 1.17 x 1022 Joules = 2.79 x 106 MegaTons.
- No crater is formed, although large fragments may strike the surface.
- What does this mean?
The air blast will arrive approximately 10.1 minutes after impact.
- Peak Overpressure: 338000 Pa = 3.38 bars = 48 psi
- Max wind velocity: 404 m/s = 903 mph
- Sound Intensity: 111 dB (May cause ear pain)
- Damage Description:
Multistory wall-bearing buildings will collapse.
Wood frame buildings will almost completely collapse.
Multistory steel-framed office-type buildings will suffer extreme frame distortion, incipient collapse.
Highway truss bridges will collapse.
Glass windows will shatter.
Cars and trucks will be overturned and displaced, requiring major repairs.
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
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