21 Astronomical Unit to Parsec
Quick answer
21 Astronomical Unit (AU) equals
0.000102 pc
To convert 21 Astronomical Units to Parsecs, multiply by 4.848137e-6. Therefore, 21 Astronomical Unit (AU) equals 0.000102 Parsec (pc).
Formula: pc = AU × 4.848137e-6. Calculation: 21 × 4.848137e-6 = 0.000102 pc.
Convert Astronomical Unit (AU) to Parsec (pc) online with our free unit converter. In length, 1 AU = 4.848137e-6 pc. Explore step-by-step conversion steps, mathematical formulas, and quick conversion reference tables below.
Worked example: converting Astronomical Unit to Parsec
- Step 1 — start with the formula. pc = AU × 0.0000048481
- Step 2 — substitute your figure. 21 AU × 4.848137e-6
- Step 3 — read the result. 21 AU = 0.000102 pc
- Step 4 — check it in reverse. AU = pc × 206,264.8062470964 returns 21.039 AU, which matches the figure you started with.
Length Converter
31 units available
21 AU = 0.000102 pc
Formula:
pc = AU × 0.0000048481With your value: 21 AU = 0.00010181 pc
How big is that?
Everyday references on a logarithmic scale, all expressed in astronomical unit so you can sanity-check the result.
Other Astronomical Unit to Parsec conversions
Astronomical Unit to Parsec Conversion Table
| Astronomical Unit (AU) | Parsec (pc) |
|---|---|
| 0.5 | 2.424068e-6 |
| 1 | 4.848137e-6 |
| 2 | 9.696274e-6 |
| 5 | 2.424068e-5 |
| 10 | 4.848137e-5 |
| 15 | 7.272205e-5 |
| 20 | 9.696274e-5 |
| 25 | 0.000121 |
| 50 | 0.000242 |
| 100 | 0.000485 |
| 250 | 0.001212 |
| 500 | 0.002424 |
| 1000 | 0.004848 |
Parsec to Astronomical Unit Conversion Table
| Parsec (pc) | Astronomical Unit (AU) |
|---|---|
| 0.5 | 103,132.403124 |
| 1 | 206,264.806247 |
| 2 | 412,529.612494 |
| 5 | 1,031,324.031235 |
| 10 | 2,062,648.062471 |
| 15 | 3,093,972.093706 |
| 20 | 4,125,296.124942 |
| 25 | 5,156,620.156177 |
| 50 | 10,313,240.312355 |
| 100 | 20,626,480.62471 |
| 250 | 51,566,201.561774 |
| 500 | 103,132,403.123548 |
| 1000 | 206,264,806.247096 |
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.
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
Parsec (pc)
Length
One parsec is 648 000/π astronomical units ≈ 3.085 677 581 × 10¹⁶ m.
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 Astronomical Unit to Parsec
To convert from Astronomical Unit (AU) to Parsec (pc), multiply the value by 4.848137e-6.
Formula: pc = AU × 0.0000048481
Reverse: AU = pc × 206,264.8062470964
Step-by-Step Example
- Start with your value in Astronomical Unit. For example: 5 AU
- Multiply by the conversion factor: 5 x 4.848137e-6
- The result is: 2.424068e-5 pc
Astronomical Unit and Parsec Relationship
Both Astronomical Unit and Parsec belong to the Astronomical system, making this an intra-system conversion within length. Since 1 Astronomical Unit represents a fraction of a Parsec (1 Parsec ≈ 2.063e+5 Astronomical Units), the Parsec is the larger measurement interval. Understanding the relationship between Astronomical Unit and Parsec is essential for accurate calculations in physics, engineering, commerce, and daily applications.
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.
About Parsec
The parsec is the distance at which one astronomical unit subtends an angle of one arcsecond, about 3.26 light years. Professional astronomers prefer it to the light year.
Common uses of Parsec: astrophysics, star catalogues, cosmology.
Frequently Asked Questions
- What is 21 Astronomical Unit in Parsec?
- 21 Astronomical Unit equals 0.000102 Parsec.
- How many Parsecs are in 1 Astronomical Unit?
- There are exactly 4.848137e-6 Parsecs in 1 Astronomical Unit. This means the conversion factor from Astronomical Unit to Parsec is 4.848137e-6.
- What is the formula to convert Astronomical Unit to Parsec?
- The formula to convert Astronomical Unit to Parsec is: pc = AU × 0.0000048481. For example, to convert 10 Astronomical Units to Parsecs, you would multiply 10 by 4.848137e-6.
- 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 is a Parsec?
- The parsec is the distance at which one astronomical unit subtends an angle of one arcsecond, about 3.26 light years. Professional astronomers prefer it to the light year.
- What are the common uses of Astronomical Unit?
- The Astronomical Unit is commonly used in planetary science, orbital mechanics, astronomy.
Related Length Conversions
Cite this page
UnitConvertLab. (2026). 21 Astronomical Unit to Parsec. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/21-astronomical_unit-to-parsec