Parsec to Roman Mile Conversion Calculator: Free Online Tool
Convert parsecs to Roman miles with our free online length converter.
Parsec to Roman Mile Calculator
How to Use the Calculator:
- Enter the value you want to convert in the 'From' field (Parsec).
- The converted value in Roman Mile will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Length category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Parsec to Roman Mile
Converting Parsec to Roman Mile involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Parsec = 2.0849e+13 Roman milesExample Calculation:
Convert 10 parsecs: 10 × 2.0849e+13 = 2.0849e+14 Roman miles
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
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What is a Parsec and a Roman Mile?
The Parsec (symbol pc) is a unit of length used to measure the enormous distances to astronomical objects outside the Solar System. One parsec is defined as the distance at which one astronomical unit (AU) – the average distance between the Earth and the Sun – subtends an angle of one arcsecond (1/3600th of a degree). This corresponds to approximately:
- 3.0857 × 10¹⁶ meters (m)
- 30.857 trillion kilometers (km)
- 19.174 trillion miles (mi)
- 206,264.8 astronomical units (AU)
- 3.26156 light-years (ly)
It is derived directly from the method of trigonometric parallax used by astronomers to measure stellar distances.
The Roman Mile (mille passus, meaning "thousand paces"; symbol m.p.) was the standard Roman unit for measuring longer distances.
It was defined as 1,000 Roman paces (passus).
Since one passus (a double step) was equal to 5 Roman feet (pes), the Roman mile was equivalent to:
- 1,000 paces (passus)
- 5,000 Roman feet (pedes)
The exact length varied slightly depending on the precise definition of the Roman foot used, but it is typically estimated as:
- Approximately 1,480 meters (m)
- Approximately 1.48 kilometers (km)
- Approximately 0.919 statute miles (mi)
- Approximately 4,856 feet (ft) (using a common estimate for the Roman foot)
Note: The Parsec is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Roman Mile belongs to the imperial/US customary system.
History of the Parsec and Roman Mile
The concept of measuring stellar distances via parallax existed long before the unit itself. The term "parsec" was coined by the British astronomer Herbert Hall Turner in 1913. He sought a convenient unit for astronomers that directly reflected the observational method. The name is a portmanteau derived from "parallax of one arcsecond". It quickly gained acceptance within the astronomical community due to its practical connection to parallax measurements, which were (and still are) a fundamental way to determine distances to nearby stars.
The Roman mile was established during the Roman Republic and Empire and was used extensively throughout Roman territories for measuring roads, distances between cities, and military movements. Roman roads were famously marked with milestones (miliarium) indicating the distance in Roman miles, often back to the Milliarium Aureum (Golden Milestone) in the Forum Romanum.
The Roman mile significantly influenced the development of the mile unit in other countries, including the English statute mile, although the lengths eventually diverged.
Common Uses for parsecs and Roman miles
Explore the typical applications for both Parsec (imperial/US) and Roman Mile (imperial/US) to understand their common contexts.
Common Uses for parsecs
The parsec is the preferred unit of distance in professional astronomy and astrophysics:
- Stellar Distances: Measuring distances to nearby stars using parallax.
- Galactic Structure: Describing distances within the Milky Way galaxy (often using kiloparsecs, kpc, where 1 kpc = 1000 pc). For example, the Sun is about 8 kpc from the Galactic Center.
- Extragalactic Distances: Measuring distances to other galaxies and galaxy clusters (often using megaparsecs, Mpc, where 1 Mpc = 1,000,000 pc). The Hubble constant, describing the expansion of the universe, is typically expressed in (km/s)/Mpc.
- Cosmology: Discussing large-scale structures and distances in the universe (using Mpc and sometimes gigaparsecs, Gpc, where 1 Gpc = 1000 Mpc).
Common Uses for Roman miles
- Historical Measurement: Used ubiquitously in the Roman Empire for all land distances.
- Historical Texts: Essential for understanding distances mentioned in Roman literature, historical accounts, and geographical works.
- Archaeology: Used to interpret Roman road networks, milestone placements, and site layouts.
Frequently Asked Questions
Questions About Parsec (pc)
What does 'Parsec' stand for?
Parsec is a blend of "parallax of one arcsecond". It represents the distance at which the parallax angle of a star is exactly one second of arc.
How is a parsec defined?
It's defined based on trigonometry. Imagine a right-angled triangle in space where the short side is the Earth-Sun distance (1 AU). The parsec is the length of the adjacent side when the angle at the distant star (the parallax angle) is exactly one arcsecond.
Is a Parsec bigger than a Light Year?
Yes, one parsec is significantly larger than one light-year.
- 1 Parsec ≈ 3.26 light-years
How many meters or kilometers are in a parsec?
One parsec is approximately:
- 3.0857 × 10¹⁶ meters
- 30.857 trillion kilometers
How many Astronomical Units (AU) are in a parsec?
One parsec is equal to approximately 206,265 AU. This number arises directly from the definition involving radians and arcseconds (specifically, the number of arcseconds in a radian).
Why do astronomers use parsecs instead of light-years?
While both are used, parsecs are often preferred in professional contexts because:
- Direct Observational Link: The parsec is derived directly from the parallax angle, a primary method for measuring distance.
- Historical Convention: It became the standard unit early in the development of stellar distance measurement.
- Convenience: Multiples like kpc and Mpc provide convenient scales for galactic and extragalactic distances.
- Definition Stability: The definition of a light-year depends slightly on the definition of a "year" (e.g., Julian year), whereas the parsec is based on the fixed AU and geometric angles.
Is the parsec an SI unit?
No, the parsec is not an SI unit. The SI unit for length is the meter (m). However, the parsec (along with the astronomical unit and light-year) is recognized by the International Astronomical Union (IAU) and is widely accepted for use in astronomy.
About Roman Mile (m.p.)
How long was a Roman Mile compared to a modern mile?
A Roman mile (approx. 1480 m) was shorter than the modern international statute mile (1609.344 m). A Roman mile is about 92% the length of a modern statute mile.
What does 'mille passus' mean?
It's Latin for "a thousand paces". Mille means thousand, and passus refers to the Roman pace (a double step of 5 Roman feet).
How many feet were in a Roman Mile?
There were 5,000 Roman feet (pedes) in one Roman mile.
Is the Roman Mile still used?
No, the Roman mile is obsolete and not used for any modern measurements. It is purely a historical unit. Modern distances are measured in kilometers or statute miles.
Conversion Table: Parsec to Roman Mile
| Parsec (pc) | Roman Mile (m.p.) |
|---|---|
| 1 | 20,849,324,324,324.324 |
| 5 | 104,246,621,621,621.62 |
| 10 | 208,493,243,243,243.25 |
| 25 | 521,233,108,108,108.1 |
| 50 | 1,042,466,216,216,216.2 |
| 100 | 2,084,932,432,432,432.5 |
| 500 | 10,424,662,162,162,162 |
| 1,000 | 20,849,324,324,324,324 |
All Length Conversions
Other Units from Length
- Meter (m)
- Kilometer (km)
- Hectometer (hm)
- Decimeter (dm)
- Centimeter (cm)
- Millimeter (mm)
- Inch (in)
- Foot (ft)
- Yard (yd)
- Mile (mi)
- Nautical Mile (NM)
- Micrometer (μm)
- Nanometer (nm)
- Light Year (ly)
- Astronomical Unit (AU)
- Angstrom (Å)
- Point (Typography) (pt)
- Mil/Thou (mil)
- Fathom (fath)
- Furlong (fur)
- Link (Gunter's) (li)
- Pace (pace)
- Span (span)
- Digit (digit)
- Cable Length (cb)
- Ell (ell)
- Finger (finger)
- Stadion (stadion)
- Chi (Chinese) (chi)
- Shaku (Japanese) (shaku)
- Li (Chinese) (li)
- Toise (toise)
- Bolt (bolt)
- Rope (rope)
- Smoot (smoot)
- Sajene (sajene)
- Ken (ken)
- Wa (wa)
- Vara (vara)
- Aln (aln)
- Cubit (Royal/Egyptian) (cubit)
- Versta (versta)
- Arpent (arpent)
- Ri (Japanese) (ri)
- Klafter (klafter)
- Yojana (yojana)
- Skein (skein)