Calculator Inputs
Formula Used
Radius: r = diameter ÷ 2
Sphere volume: V = 4 ÷ 3 × π × r³ × shape factor
Bulk density: density × (1 − porosity ÷ 100)
Mass: m = V × bulk density
Kinetic energy: E = 0.5 × m × v²
Angle adjusted energy: E × sin²(angle)
Effective impact energy: angle adjusted energy × efficiency ÷ 100
TNT megatons: effective joules ÷ 4.184 × 10¹⁵
How to Use This Calculator
- Keep the diameter at 2000 meters for the requested impactor.
- Enter a density that matches the likely material.
- Enter velocity in kilometers per second.
- Use 90 degrees for a vertical strike.
- Use porosity to reduce bulk mass.
- Use efficiency to estimate coupled impact energy.
- Press Calculate to show the result above the form.
- Export the result with the CSV or PDF button.
Example Data Table
| Case | Diameter | Density | Velocity | Angle | Effective Energy | TNT Yield |
|---|---|---|---|---|---|---|
| Default rocky case | 2, m | 3, kg/m³ | 20 km/s | 45° | 1.257E+21 J | 300.343 Gt |
| Iron rich body | 2, m | 7,8 kg/m³ | 15 km/s | 60° | 2.757E+21 J | 658.878 Gt |
| Porous comet like body | 2, m | 6 kg/m³ | 30 km/s | 35° | 1.935E+20 J | 46.243 Gt |
| Slower stony case | 2, m | 2,5 kg/m³ | 12 km/s | 45° | 3.054E+20 J | 72.983 Gt |
Article: Understanding a 2000 Meter Impactor
Overview
A 2000 meter impactor is a very large body. Its energy depends on mass and speed. Diameter gives volume. Density turns volume into mass. Velocity then controls the final result with a square relationship. That makes speed the most sensitive input in this calculator.
Main Inputs
The tool begins with a spherical shape. It sets the diameter to 2000 meters by default. You can change it, but that value stays ready for this case. The sphere formula gives volume from radius. Bulk density is then adjusted by porosity. A porous object has less solid material in the same outside size.
Energy Output
Impact energy is kinetic energy. The main result is shown in joules. The same energy is also converted into kilotons, megatons, and gigatons of TNT. These units make large numbers easier to compare. The calculator also shows mass, volume, momentum, and a vertical component based on the selected angle.
Angle and Efficiency
Angle matters because a shallow strike spreads energy across a longer path. A vertical strike focuses more energy downward. The effective energy result applies the angle factor and the selected coupling efficiency. This value is useful when you want a conservative working estimate, not just the total moving energy.
Material Choice
Use realistic densities when possible. A comet like body may be light. A stony asteroid is usually heavier. An iron rich body can be much denser. Small density changes are important, because a two kilometer sphere has a huge volume.
Velocity Effect
Velocity should be entered in kilometers per second. Many impact scenarios use speeds from 11 to 30 kilometers per second. A fast object can produce far more energy than a slower object with the same size. Doubling speed increases kinetic energy four times.
Practical Notes
This calculator is a mathematical estimator. It does not replace a full planetary impact model. Real outcomes also depend on strength, rotation, entry breakup, target geology, ocean depth, atmosphere, and impact location. Still, it gives a strong first estimate. It helps students, writers, researchers, and educators explore how diameter, speed, and material properties combine. Start with the default case, test one variable at a time, and compare the exported results with the example table. Keep notes on each run so later changes remain clear, traceable, and easy for future review work.
FAQs
1. What does this calculator estimate?
It estimates kinetic energy for a large impactor. It also converts the effective energy into TNT units. The result depends on diameter, density, velocity, angle, porosity, shape, and efficiency.
2. Why is the default diameter 2000 meters?
The requested case is an impactor measuring 2000 meters in diameter. The input remains editable, so you can test nearby sizes or compare smaller and larger objects.
3. Which input changes energy the most?
Velocity has a very strong effect because kinetic energy uses velocity squared. If velocity doubles, energy becomes four times larger, assuming mass stays unchanged.
4. What density should I use?
Use lower density for porous comet like objects. Use medium density for stony bodies. Use higher density for iron rich bodies. The example table gives useful starting points.
5. What does porosity mean?
Porosity estimates empty space inside the body. Higher porosity lowers bulk density, mass, and energy. It is useful for loose, fractured, icy, or rubble pile objects.
6. What does coupling efficiency mean?
Coupling efficiency estimates how much angle adjusted energy is transferred into the impact event. Use 100 percent for a simple upper estimate. Use lower values for conservative scenarios.
7. Is this a crater size calculator?
No. It focuses on energy. Crater size requires more variables, including target rock, gravity, impactor strength, entry breakup, and impact location. Use a crater model for that task.
8. Can I export my result?
Yes. Use Download CSV for spreadsheet work. Use Download PDF for a simple report. Both options help save inputs and calculated output for later review.