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Convert Light Year to Picometer (ly to pm) instantly with accurate, readable results.
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Light-year (ly) - astronomical distance
Light-year is an astronomical distance equal to the distance light travels in vacuum in one Julian year. Used for interstellar and intergalactic scales; based on c = 299,792,458 m/s and a Julian year of 365.25 days (31,557,600 s)
- Symbol: ly
- System: Astronomical (non-SI, accepted for use with SI)
- Defined relation: 1 ly = c × 31,557,600 s = 9.4607304725808×10^15 m ≈ 9.4607×10^12 km
- Other relations: 1 ly ≈ 63,241.077 AU; 1 ly ≈ 0.306601 pc; 1 pc ≈ 3.26156 ly
- Typical examples: Proxima Centauri ~4.2465 ly; Milky Way diameter ~1.0×10^5 ly; Andromeda Galaxy ~2.5×10^6 ly
Picometer (pm) — SI unit equal to one trillionth of a meter
Used to express atomic and subatomic dimensions such as bond lengths and ionic/atomic radii in chemistry and materials science
- Symbol: pm
- System: SI derived unit
- Exact relations: 1 pm = 10⁻¹² m = 0.001 nm = 10⁻⁶ µm = 0.01 Å = 1,000 fm
- Imperial/US equivalents: 1 pm ≈ 0.00000000003937007874 in
- Typical examples: covalent bond lengths ~100–200 pm; Bohr radius of hydrogen ~53 pm; atomic radii tens to a few hundred pm