21 Angstrom to Astronomical Unit
Quick answer
21 Angstrom (Å) equals
1.403763e-20 AU
To convert 21 Angstroms to Astronomical Units, multiply by 6.684587e-22. Therefore, 21 Angstrom (Å) equals 1.403763e-20 Astronomical Unit (AU).
Formula: AU = Å × 6.684587e-22. Calculation: 21 × 6.684587e-22 = 1.403763e-20 AU.
Convert Angstrom (Å) to Astronomical Unit (AU) online with our free unit converter. In length, 1 Å = 6.684587e-22 AU. Explore step-by-step conversion steps, mathematical formulas, and quick conversion reference tables below.
Worked example: converting Angstrom to Astronomical Unit
- Step 1 — start with the formula. AU = Å × 6.684587e-22
- Step 2 — substitute your figure. 21 Å × 6.684587e-22
- Step 3 — read the result. 21 Å = 1.403763e-20 AU
- Step 4 — check it in reverse. Å = AU × 1.495979e+21 returns 21 Å, which matches the figure you started with.
Length Converter
31 units available
21 Å = 1.403763e-20 AU
Formula:
AU = Å × 6.684587e-22With your value: 21 Å = 1.403763e-20 AU
How big is that?
Everyday references on a logarithmic scale, all expressed in angstrom so you can sanity-check the result.
Other Angstrom to Astronomical Unit conversions
Angstrom to Astronomical Unit Conversion Table
| Angstrom (Å) | Astronomical Unit (AU) |
|---|---|
| 0.5 | 3.342294e-22 |
| 1 | 6.684587e-22 |
| 2 | 1.336917e-21 |
| 5 | 3.342294e-21 |
| 10 | 6.684587e-21 |
| 15 | 1.002688e-20 |
| 20 | 1.336917e-20 |
| 25 | 1.671147e-20 |
| 50 | 3.342294e-20 |
| 100 | 6.684587e-20 |
| 250 | 1.671147e-19 |
| 500 | 3.342294e-19 |
| 1000 | 6.684587e-19 |
Astronomical Unit to Angstrom Conversion Table
| Astronomical Unit (AU) | Angstrom (Å) |
|---|---|
| 0.5 | 7.479894e+20 |
| 1 | 1.495979e+21 |
| 2 | 2.991957e+21 |
| 5 | 7.479894e+21 |
| 10 | 1.495979e+22 |
| 15 | 2.243968e+22 |
| 20 | 2.991957e+22 |
| 25 | 3.739947e+22 |
| 50 | 7.479894e+22 |
| 100 | 1.495979e+23 |
| 250 | 3.739947e+23 |
| 500 | 7.479894e+23 |
| 1000 | 1.495979e+24 |
Where these values come from
Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.
Angstrom (Å)
Length
Traceable to the metre, defined by fixing the speed of light in vacuum at 299 792 458 m/s. Imperial lengths derive from the 1959 international yard (0.9144 m exactly).
Source: BIPM, The International System of Units (SI), 9th edition, 2019 (updated 2024)
Bureau International des Poids et Mesures · Reviewed 2026-07-01
Astronomical Unit (AU)
Length
The astronomical unit is exactly 149 597 870 700 m (IAU Resolution B2, 2012).
Source: IAU Resolution B2 (2012) — definition of the astronomical unit; IAU B2 (2015) nominal values
International Astronomical Union · Reviewed 2026-07-01
How to Convert Angstrom to Astronomical Unit
To convert from Angstrom (Å) to Astronomical Unit (AU), multiply the value by 6.684587e-22.
Formula: AU = Å × 6.684587e-22
Reverse: Å = AU × 1.495979e+21
Step-by-Step Example
- Start with your value in Angstrom. For example: 5 Å
- Multiply by the conversion factor: 5 x 6.684587e-22
- The result is: 3.342294e-21 AU
Angstrom and Astronomical Unit Relationship
This calculation facilitates standardized conversion between recognized units of length. Since 1 Angstrom represents a fraction of a Astronomical Unit (1 Astronomical Unit ≈ 1.496e+21 Angstroms), the Astronomical Unit is the larger measurement interval. Understanding the relationship between Angstrom and Astronomical Unit is essential for accurate calculations in physics, engineering, commerce, and daily applications.
About Angstrom
The angstrom (Å) equals 10⁻¹⁰ metres, or 0.1 nanometres — roughly the diameter of a hydrogen atom, which is why it survives in crystallography and spectroscopy.
Common uses of Angstrom: crystallography, atomic physics, semiconductors.
About Astronomical Unit
The astronomical unit (AU) is defined as exactly 149,597,870,700 metres, close to the mean Earth–Sun distance. It is the natural yardstick for the Solar System.
Common uses of Astronomical Unit: planetary science, orbital mechanics, astronomy.
Frequently Asked Questions
- What is 21 Angstrom in Astronomical Unit?
- 21 Angstrom equals 1.403763e-20 Astronomical Unit.
- How many Astronomical Units are in 1 Angstrom?
- There are exactly 6.684587e-22 Astronomical Units in 1 Angstrom. This means the conversion factor from Angstrom to Astronomical Unit is 6.684587e-22.
- What is the formula to convert Angstrom to Astronomical Unit?
- The formula to convert Angstrom to Astronomical Unit is: AU = Å × 6.684587e-22. For example, to convert 10 Angstroms to Astronomical Units, you would multiply 10 by 6.684587e-22.
- What is a Angstrom?
- The angstrom (Å) equals 10⁻¹⁰ metres, or 0.1 nanometres — roughly the diameter of a hydrogen atom, which is why it survives in crystallography and spectroscopy.
- What is a Astronomical Unit?
- The astronomical unit (AU) is defined as exactly 149,597,870,700 metres, close to the mean Earth–Sun distance. It is the natural yardstick for the Solar System.
- What are the common uses of Angstrom?
- The Angstrom is commonly used in crystallography, atomic physics, semiconductors.
Related Length Conversions
Cite this page
UnitConvertLab. (2026). 21 Angstrom to Astronomical Unit. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/21-angstrom-to-astronomical_unit