Parsec
A parsec (pc) is a unit of distance used in astronomy, equal to about 3.26 light-years or roughly 31 trillion kilometers. The name “parsec” comes from “parallax of one arcsecond,” referring to the method astronomers use to measure distances to nearby stars based on their apparent shift when viewed from different positions in Earth’s orbit. Parsecs are commonly used to measure distances to stars and galaxies. For example, the nearest star system, Alpha Centauri, is about 1.3 parsecs away. The symbol for parsec is "pc". It’s a convenient unit for expressing large astronomical distances beyond the reach of light-years.
Caliber
Caliber is a term used to describe the internal diameter of a cylindrical object, most commonly the inside diameter of a gun barrel or firearm bore. It is typically measured in inches or millimeters.
In firearms, caliber indicates the diameter of the bullet or projectile that can be fired from the barrel (e.g., a .45 caliber means the barrel’s internal diameter is 0.45 inches).
In other contexts, such as engineering or piping, caliber can refer more generally to the diameter or thickness of tubes or cylindrical objects.
Key points:
Caliber = internal diameter of a barrel or tube
Measured in inches or millimeters
Important for firearm specifications and ammunition compatibility
Also used in engineering and manufacturing
Caliber is crucial for matching ammunition to firearms and for defining performance characteristics like velocity and accuracy.
No conversions available for length.