Convert Nanowatt per square metre to International table BTU per second per square foot
Convert Nanowatt per square metre (nW/m²) to International table BTU per second per square foot (BTU(IT)/(s·ft²)) instantly and accurately.
Conversion Formula
BTU(IT)/(s·ft²) = nW/m² × 8.805509184e-14
About Nanowatt per square metre
The nanowatt per square metre (nW/m²) equals 10⁻⁹ W/m². Used in astrophysics and cosmology for quantifying extremely weak radiation fields, such as cosmic microwave background intensity and residual thermal emission from near-absolute-zero objects. Relevant in precision cryogenic sensor calibration. 1 nW/m² = 10⁻⁹ W/m² = 10³ pW/m².
About International table BTU per second per square foot
The international table BTU per second per square foot (BTU(IT)/(s·ft²)) equals 1055.05585262/0.09290304 ≈ 11357 W/m² (= 3600 × BTU(IT)/(h·ft²)). Used for extreme heat flux: atmospheric re-entry aerodynamic heating, solid rocket nozzle throat, and nuclear reactor thermal hydraulics design. 1 BTU(IT)/(s·ft²) ≈ 11357 W/m².
Quick Reference Table
| Nanowatt per square metre (nW/m²) | International table BTU per second per square foot (BTU(IT)/(s·ft²)) |
|---|---|
| 1 nW/m² | 8.806 × 10-14 BTU(IT)/(s·ft²) |
| 2 nW/m² | 1.761 × 10-13 BTU(IT)/(s·ft²) |
| 5 nW/m² | 4.403 × 10-13 BTU(IT)/(s·ft²) |
| 10 nW/m² | 8.806 × 10-13 BTU(IT)/(s·ft²) |
| 25 nW/m² | 2.201 × 10-12 BTU(IT)/(s·ft²) |
| 50 nW/m² | 4.403 × 10-12 BTU(IT)/(s·ft²) |
| 100 nW/m² | 8.806 × 10-12 BTU(IT)/(s·ft²) |