Convert Megameter to Terameter
Convert megameters to terameters instantly. 1 megameter = 1e-6 terameter — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Terameter to Megameter converter for the reverse conversion.
Units explained
Megameter
A megameter is a metric unit of length equal to one million meters (1×10⁶ m, or 1,000 km). It is occasionally used in geophysics and astronomy when expressing planetary-scale distances in SI units.
The megameter uses the SI prefix mega- (from Greek megas, great), adopted by the CGPM in 1960 to denote multiplication by one million.
Megameters appear in geophysics (Earth's mean radius is 6.371 Mm), planetary science, and large-scale civil engineering planning. The unit is less common than the kilometer for everyday geographic distances.
SI prefix mega- adopted in 1960; the megameter is the standard SI prefix unit for distances comparable to planetary radii.
Terameter
A terameter is a metric unit of length equal to one trillion meters (1×10¹² m). It is rare in everyday use but appears in astronomy when expressing solar-system-scale distances in SI units.
The terameter uses the SI prefix tera- (from Greek teras, monster), adopted by the CGPM in 1960 to denote multiplication by one trillion (10¹²).
Terameters are occasionally used in astronomy to express distances on the order of Earth–Sun (~0.15 Tm or 1 AU) and outer-planet distances. The astronomical unit (AU) and light-hour are more common in practice.
SI prefix tera- adopted in 1960; the terameter is the standard SI prefix unit for distances comparable to inter-planetary scales but is less common than the AU in working astronomy.
Megameter to Terameter conversion formula
The relationship between megameters and terameters:
To convert megameters to terameters, multiply the value in megameters by 1e-6. To reverse, multiply terameters by 1000000.
How to use this converter
Type a value into the calculator. The result in terameters updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Terameter to Megameter converter for the reverse direction.
Step-by-step: convert megameters to terameters
- Write down the value in megameters (Mm).
- Multiply that value by the factor 1e-6.
- The product is the equivalent value in terameters (Tm).
- To reverse, multiply the terameter value by 1000000.
Worked examples
Example 1 — Convert 1 Mm to Tm:
1 × 1e-6 = 1e-6 Tm
Example 2 — Convert 100 Mm to Tm:
100 × 1e-6 = 1e-4 Tm
Megameter to Terameter conversion table
Standard reference values for converting megameters to terameters:
| Megameter [Mm] | Terameter [Tm] |
|---|---|
| 0.01 | 1e-8 |
| 0.1 | 1e-7 |
| 1 | 1e-6 |
| 2 | 2e-6 |
| 3 | 3e-6 |
| 4 | 4e-6 |
| 5 | 5e-6 |
| 10 | 1e-5 |
| 20 | 2e-5 |
| 30 | 3e-5 |
| 40 | 4e-5 |
| 50 | 5e-5 |
| 100 | 1e-4 |
| 500 | 0.0005 |
| 1000 | 0.001 |
Frequently asked questions
How many terameters is 1 megameter?
How do I convert megameters to terameters?
How do I convert terameters back to megameters?
How many terameters is 100 megameters?
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Sources & references
Conversion factor (1 Mm = 1e-6 Tm) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.