# Astronomical Units to Angstroms (au to A) Source: https://www.unitconvertercalculator.com/length/astronomical-units-to-angstroms/ **1 au = 1.495978707E+21 A** One astronomical unit equals approximately 1.496 × 1021 ångströms - about 1.5 sextillion. This is the reverse of the ångströms-to-AU conversion and spans the full range from planetary orbit scale down to atomic bond scale. The number is so enormous it illustrates why different units exist for different scales. ## Formula Convert Astronomical Units to Angstroms ## Conversion Table | Astronomical Units (au) | Angstroms (A) | |---|---| | 1.0E-15 au | 1495978.707 A | | 1.0E-14 au | 14959787.07 A | | 1.0E-13 au | 149597870.7 A | | 1.0E-12 au | 1495978707 A | | 1.0E-11 au | 14959787070 A | | 1.0E-10 au | 149597870700 A | | 1.0E-9 au | 1495978707000 A | | 1.0E-8 au | 14959787070000 A | | 1.0E-7 au | 1.495978707E+14 A | | 1.0E-6 au | 1.495978707E+15 A | | 1.0E-5 au | 1.495978707E+16 A | ## 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. ### Angstrom (A) One ten-billionth of a meter (0.1 nanometers). Named after Anders Jonas Angstrom. Used in crystallography, spectroscopy, and atomic physics. ## Background The Earth-Sun distance (1 AU) expressed in ångströms is about 1,496,000,000,000,000,000,000 - a number with 21 digits. Mars at 1.52 AU is roughly 2.27 × 1021 Å from the Sun. These conversions appear only in educational contexts demonstrating the hierarchy of measurement scales. ## Good to Know This conversion takes us from the realm of NASA missions and planetary science down to the realm of chemistry labs and X-ray crystallography. The two communities measure in completely different units for good reason. ## FAQ ### How many ångströms are in 1 AU? One AU contains approximately 1.496 × 1021 ångströms (about 1.5 sextillion). This enormous number reflects the 21-order-of-magnitude gap between solar system and atomic scales. ### How do I convert AU to ångströms? Multiply the AU value by 1.496 × 1021. For example, 5 AU (roughly Jupiter's distance) = 7.48 × 1021 Å. ### Why would I convert AU to ångströms? Only for educational purposes to demonstrate scale. No scientific measurement requires expressing planetary distances in atomic units. Astronomers use AU, light-years, or parsecs for solar system and stellar distances. ## Non-Frequently Asked Questions ### If I shrunk the solar system to fit on my desk, how big would an atom be? If 1 AU (Earth-Sun distance) shrank to 1 meter (desk-width), an atom at 1 angstrom would shrink to about 10-16 meters, or 100 attometers. That is smaller than a proton. You could not detect it even with the most powerful particle accelerator. ### Are there more angstroms in an AU or stars in the galaxy? One AU contains about 1.496 x 1021 angstroms (1.5 sextillion). The Milky Way has about 100-400 billion stars. Angstroms in an AU outnumber galaxy stars by a factor of about 5 billion. The small stuff adds up. ### Could you lay atoms from Earth to the Sun? You would need about 1021 atoms end-to-end to span 1 AU. A human body contains about 7 x 1027 atoms, enough to stretch from Earth to the Sun about 7 million times. You contain multitudes - and then some. ## Related Articles - [Why We Measure: The Deepest Urge in Human Civilisation](https://www.unitconvertercalculator.com/blog/why-we-measure) - [The Map Is Not the Territory: Why Every Measurement Is Wrong](https://www.unitconvertercalculator.com/blog/the-map-is-not-the-territory) - [Zero: The Most Dangerous Number in Measurement](https://www.unitconvertercalculator.com/blog/zero-the-most-dangerous-number-in-measurement) - [The Body as a Ruler: Every Measurement Unit That Came From Us](https://www.unitconvertercalculator.com/blog/the-body-as-a-ruler) - [The Speed of Everything: How We Measure From Glaciers to Light](https://www.unitconvertercalculator.com/blog/the-speed-of-everything) - [15 Obscure Measurement Units You've Never Heard Of (But Still Need)](https://www.unitconvertercalculator.com/blog/obscure-measurement-units-guide) - [When Measurements Go Wrong - Disasters, Blunders and Happy Accidents](https://www.unitconvertercalculator.com/blog/when-measurements-go-wrong) - [The Surprising Stories Behind Everyday Units of Measurement](https://www.unitconvertercalculator.com/blog/stories-behind-measurement-units) - [Metric vs. Imperial - The Complete Guide to the World's Two Measurement Systems](https://www.unitconvertercalculator.com/blog/metric-vs-imperial-complete-guide) - [Length & Distance Conversion Guide - Meters, Feet, Miles & Kilometers](https://www.unitconvertercalculator.com/blog/length-and-distance-guide) ## See Also - [Angstroms to Astronomical Units](https://www.unitconvertercalculator.com/length/angstroms-to-astronomical-units/)