# Astronomical Units to Millimeters (au to mm)

Source: https://www.unitconvertercalculator.com/length/astronomical-units-to-millimeters/

**1 au = 1.495978707E+14 mm**

One astronomical unit equals approximately 1.496 x 1014 millimeters, or about 150 trillion millimeters. This conversion expresses the Earth-Sun distance in the precision engineering unit used for manufacturing tolerances, screw threads, and technical specifications.

## Formula

Convert Astronomical Units to Millimeters

## Conversion Table

| Astronomical Units (au) | Millimeters (mm) |
|---|---|
| 1.0E-13 au | 14.95978707 mm |
| 1.0E-12 au | 149.5978707 mm |
| 1.0E-11 au | 1495.978707 mm |
| 1.0E-10 au | 14959.78707 mm |
| 1.0E-9 au | 149597.8707 mm |
| 1.0E-8 au | 1495978.707 mm |
| 1.0E-7 au | 14959787.07 mm |
| 1.0E-6 au | 149597870.7 mm |
| 1.0E-5 au | 1495978707 mm |
| 0.0001 au | 14959787070 mm |
| 0.001 au | 149597870700 mm |

## Units

### Astronomical Unit (au)

Exactly 149,597,870,700 meters by IAU 2012 definition. Roughly the average distance from the Earth to the Sun. Used for distances within our solar system.

### Millimeter (mm)

A metric unit of length equal to one thousandth of a meter. Used in engineering, manufacturing, and precise measurements.

## Background

The Earth-Sun distance in millimeters is about 149,597,870,700,000 mm. A 10mm wrench is 6.7 x 10-14 AU long. While no engineer needs planetary distances in millimeters, the conversion illustrates the enormous gap between human-scale precision (millimeters) and astronomical distances (AU).

## Good to Know

Engineering drawings specify parts in millimeters. Orbital mechanics specifies trajectories in AU. Both are precision disciplines, but their measurement scales differ by 14 orders of magnitude.

## FAQ

### How many millimeters are in 1 AU?

One AU contains approximately 1.496 x 1014 millimeters (about 150 trillion mm). Since 1 AU = 149,597,870,700 m and 1 m = 1,000 mm, multiply.

### How do I convert AU to millimeters?

Multiply the AU value by 1.496 x 1014. For practical purposes, this conversion is never needed. AU is for astronomy, mm is for engineering.

### Is this conversion ever practical?

No. Millimeters are for machining tolerances and technical drawings. AU is for planetary orbits. They serve completely different purposes at completely different scales.

## Non-Frequently Asked Questions

### If I shrunk the solar system to fit on my desk, how big would Earth's orbit be?

If 1 AU = 1 meter (1,000 mm), Earth orbits at 1 m from a pinhead Sun. Jupiter would be at 5.2 m (across the room). Neptune at 30 m (down the street). The actual solar system in millimeters would be 149.6 trillion mm across for just Earth's orbit.

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## See Also

- [Millimeters to Astronomical Units](https://www.unitconvertercalculator.com/length/millimeters-to-astronomical-units/)