An astronomical unit is the mean Earth-Sun distance.
Astronomical units to Meters Converter — AU to m
Convert Astronomical unit (AU) to Meter (m) using the exact conversion factor (1 astronomical unit = 149,597,870,700 meter). See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Astronomical units to Meters converter
Converter
Length Converter
Convert SI, imperial, US customary, astronomical, scientific, and historical length units.
Context values
Some unit families need one extra value for a physically accurate result.
The meter is the SI base unit of length.
Result = input x 1.49597871e+11 / 1.
Length uses the meter as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Astronomical units to Meters
Astronomical unit and Meter both measure length. Astronomical unit is typically associated with used internationally in astronomy for solar-system-scale distances., while Meter is typically associated with standard length unit worldwide except the US.
Formula
meters = astronomical units × 149597870700
This factor comes from each unit's defined relationship to the category's base unit: 1 astronomical unit equals 149597870700 base units, and 1 meter equals 1 base unit, so dividing one by the other gives the direct astronomical unit-to-meter factor of 149597870700.
Simple example
1 AU × 149597870700 = 149,597,870,700 m
1 astronomical unit = 149,597,870,700 meters.
Real-world example
10 AU × 149597870700 = 1.495979e+12 m
10 astronomical units = 1.495979e+12 meters.
Conversion table
| Astronomical unit (AU) | Meter (m) |
|---|---|
| 1 AU | 149,597,870,700 m |
| 5 AU | 747,989,353,500 m |
| 10 AU | 1.495979e+12 m |
| 21.0975 AU | 3.156141e+12 m |
| 42.195 AU | 6.312282e+12 m |
| 100 AU | 1.495979e+13 m |
Reverse conversion: Meter to Astronomical unit
1 m × 6.684587e-12 = 6.684587e-12 AU
1 meter = 6.684587e-12 astronomical units.
astronomical units = meters × 6.684587e-12
For a page dedicated to this direction, see Meter to Astronomical unit.
Astronomical unit vs. Meter
| Aspect | Astronomical unit | Meter |
|---|---|---|
| Family | Non-SI unit accepted for use with SI (astronomical) | SI base unit |
| Typical use | Measuring distances within the solar system (planetary orbits) | Universal scientific and everyday length measurement outside the US |
| Where it's used | Used internationally in astronomy for solar-system-scale distances. | Standard length unit worldwide except the US |
Understanding the Astronomical unit
Astronomical unit (AU) measures distance. The astronomical unit is defined as exactly 149,597,870,700 meters, close to the average Earth-Sun distance. It is classified as a Non-SI unit accepted for use with SI (astronomical).
Where it's used: Used internationally in astronomy for solar-system-scale distances.
Uses of the Astronomical unit today
- Measuring distances within the solar system (planetary orbits)
- Astronomical calculations and spacecraft navigation
- Popular science communication about the solar system
History of the Astronomical unit
The astronomical unit originated from 17th-19th century attempts to measure the Earth-Sun distance, refined over time using transits of Venus and later radar and spacecraft ranging.
In 2012, the International Astronomical Union fixed the AU at exactly 149,597,870,700 meters, replacing its earlier definition (tied to gravitational calculations) with a simple fixed distance, independent of the slightly-variable actual Earth-Sun distance.
Historical origin. Astronomical unit was not the invention of a single named person; it developed through the process described above.
Understanding the Meter
Meter (m) measures distance. The meter is the SI base unit of length, currently defined via the fixed speed of light. It is classified as a SI base unit.
Where it's used: Standard length unit worldwide except the US
Uses of the Meter today
- Universal scientific and everyday length measurement outside the US
- Construction, engineering, and manufacturing internationally
History of the Meter
Defined during the French Revolutionary metric reforms as one ten-millionth of the distance from the North Pole to the Equator, the meter has been redefined several times for precision — a platinum-iridium bar (1889), a krypton-86 wavelength (1960), and since 1983, the distance light travels in 1/299,792,458 of a second.
Historical origin. Meter was not the invention of a single named person; it developed through the process described above.
Astronomical unit — sources
- IAU Resolution B2 (2012) — Fixes the astronomical unit at exactly 149,597,870,700 meters.
Meter — sources
- BIPM — The metre (SI base unit) — Current definition and history of the meter.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many meters are in 1 astronomical unit?
1 astronomical unit equals 149,597,870,700 meters, using the exact defined conversion factor rather than an estimate.
How do I convert astronomical unit to meter?
Multiply the astronomical unit value by 149597870700. The converter above does this instantly to whatever precision you set.
How do I convert meter back to astronomical unit?
Use the reverse factor: 1 meter equals 6.684587e-12 astronomical units. You can also use the swap control in the converter above to flip the direction instantly.
What is a astronomical unit?
Astronomical unit (AU) measures distance. The astronomical unit is defined as exactly 149,597,870,700 meters, close to the average Earth-Sun distance. It is classified as a Non-SI unit accepted for use with SI (astronomical).
What is a meter?
Meter (m) measures distance. The meter is the SI base unit of length, currently defined via the fixed speed of light. It is classified as a SI base unit.
Is the astronomical unit to meter conversion exact?
Yes. The astronomical unit is defined as exactly 149,597,870,700 meters, close to the average Earth-Sun distance. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
Where is the astronomical unit still used today?
Used internationally in astronomy for solar-system-scale distances.