Smoot to Parsec Conversion Calculator: Free Online Tool
Convert smoots to parsecs with our free online length converter.
Smoot to Parsec Calculator
How to Use the Calculator:
- Enter the value you want to convert in the 'From' field (Smoot).
- The converted value in Parsec 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 Smoot to Parsec
Converting Smoot to Parsec involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Smoot = 5.5151e-17 parsecsExample Calculation:
Convert 10 smoots: 10 × 5.5151e-17 = 5.5151e-16 parsecs
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.
Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.
What is a Smoot and a Parsec?
The Smoot is a non-standard, humorous unit of length created as part of an MIT fraternity prank in October 1958. It is defined by the height of Oliver R. Smoot (MIT class of 1962) at the time of the prank, which was 5 feet 7 inches.
This equates to:
- 67 inches (in)
- 1.7018 meters (m)
- Approximately 1.86 yards (yd)
Unlike standardized units, the Smoot is intrinsically tied to a specific individual's height at a particular moment and serves primarily as a cultural artifact and inside joke, particularly within the MIT community.
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.
Note: The Smoot is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Parsec belongs to the imperial/US customary system.
History of the Smoot and Parsec
The Smoot unit originated in October 1958 during the pledge activities of the Lambda Chi Alpha fraternity at MIT. Pledges were tasked with measuring the length of the Harvard Bridge, which connects Boston and Cambridge, Massachusetts, over the Charles River.
Instead of using conventional measuring tools, the fraternity members decided to use one of their pledges, Oliver Smoot, as the unit of measure. They repeatedly laid him down end-to-end across the bridge, marking off increments in paint. His companions carried him or helped him move for each new measurement.
The final measurement determined the bridge's length to be 364.4 Smoots "plus or minus one ear". The "ear" indicated the uncertainty of the measurement, adding to the absurdity and humor of the event.
The painted markings on the bridge became a local landmark. They have been maintained and periodically repainted over the decades, often unofficially by members of the fraternity or other MIT affiliates. The Cambridge Police Department traditionally tolerates the markings because, among other reasons, they serve as useful reference points for identifying locations along the bridge.
Interestingly, Oliver R. Smoot later became a prominent figure in standards organizations, serving as Chairman of the American National Standards Institute (ANSI) and President of the International Organization for Standardization (ISO), an ironic twist given his namesake unit's non-standard nature.
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.
Common Uses for smoots and parsecs
Explore the typical applications for both Smoot (imperial/US) and Parsec (imperial/US) to understand their common contexts.
Common Uses for smoots
The Smoot is not used for any official, scientific, or commercial measurements. Its use is primarily cultural and humorous:
- Harvard Bridge Markings: The painted markings on the bridge sidewalk are its most famous application, indicating distance in Smoots from the Boston side. They are a well-known local landmark.
- MIT Culture and Slang: Used humorously within the MIT community and sometimes in the broader Boston area as a quirky local reference.
- Digital Recognition: The unit gained wider recognition when it was included as a unit of measurement in Google Calculator and Google Earth's ruler tool.
- Popular Culture: Occasionally referenced in media or tech circles as an example of a non-standard or humorous unit.
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).
Frequently Asked Questions
Questions About Smoot (smoot)
How long is a Smoot?
One Smoot is exactly the height of Oliver R. Smoot in 1958:
- 5 feet 7 inches
- 67 inches
- 1.7018 meters
Is the Smoot an official or standardized unit?
No, the Smoot is not an official or standardized unit of measurement in any system (Imperial, US customary, or SI). It is a non-standard, humorous unit originating from a specific event.
Why is the bridge measurement "plus or minus one ear"?
The "plus or minus one ear" (often written as ± εar) reflects the humorous imprecision of the original measurement method using a person. It signifies the margin of error in a whimsical way, possibly referencing the difficulty of the final partial measurement or simply adding to the prank's absurdity.
Are the Smoot markings still on the Harvard Bridge?
Yes, the markings are traditionally repainted periodically (often by Lambda Chi Alpha members) and are considered a fixture of the bridge. During bridge renovations in 2011, the Massachusetts Department of Transportation restored the markings, acknowledging their cultural significance.
How does the Smoot compare to standard units?
- 1 Smoot = 1.7018 meters
- 1 Meter ≈ 0.5876 Smoots
- 1 Smoot = 5.583 feet (5 feet 7 inches)
- 1 Foot ≈ 0.1791 Smoots
Is the Smoot an SI unit?
No, the Smoot is not an SI unit. It is a non-standard, informal unit. The SI base unit for length is the meter (m).
What did Oliver Smoot think of the unit?
Oliver Smoot generally embraced his namesake unit with good humor throughout his life and career, often participating in events related to it at MIT.
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.
Conversion Table: Smoot to Parsec
| Smoot (smoot) | Parsec (pc) |
|---|---|
| 1 | 0 |
| 5 | 0 |
| 10 | 0 |
| 25 | 0 |
| 50 | 0 |
| 100 | 0 |
| 500 | 0 |
| 1,000 | 0 |
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)
- Roman Mile (m.p.)
- Stadion (stadion)
- Chi (Chinese) (chi)
- Shaku (Japanese) (shaku)
- Li (Chinese) (li)
- Toise (toise)
- Bolt (bolt)
- Rope (rope)
- 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)