UT1

Học thuật
Thân thiện
Definition
  1. Noun:
    • Coordinated Universal Time (UTC): "UT1" is a specific measure of time based on the Earth's rotation. It represents the local mean solar time at the prime meridian (0° longitude) in Greenwich, England. Unlike time zones, UT1 is theoretically the same everywhere on Earth at a given moment.
Usage

"UT1" is a technical term used primarily in astronomy, geodesy, and precise timekeeping. It is not used in everyday conversation. It is often contrasted with other time scales like UTC (Coordinated Universal Time), which is adjusted with leap seconds to stay within 0.9 seconds of UT1.

Examples
  • Noun:
    • Astronomers use UT1 to calculate the precise orientation of the Earth for celestial navigation.
    • The difference between UTC and UT1 is monitored and corrected by the insertion of leap seconds.
Advanced Usage
  • "UT1-UTC": This refers to the difference, or "delta," between Universal Time (UT1) and Coordinated Universal Time (UTC). This value is published by the International Earth Rotation and Reference Systems Service (IERS).
    • The IERS Bulletin D provides the current value of UT1-UTC.
Variants and Related Words
  • Universal Time (UT): A broader term; UT1 is the principal form of Universal Time.
  • UTC (Coordinated Universal Time): The primary time standard by which the world regulates clocks and time. It is kept within 0.9 seconds of UT1 using leap seconds.
  • Greenwich Mean Time (GMT): Often used informally to refer to UTC, but historically it was a time zone and a precursor to UT.
Synonyms
  • Universal Time (UT): The general category.
  • Greenwich Mean Time (GMT): In casual, non-technical contexts, GMT is sometimes used synonymously, though this is not precisely accurate.
Notes
  • Not an Idiom or Phrasal Verb: "UT1" is a scientific acronym and does not have idiomatic uses or function as part of phrasal verbs.
  • Meaning: It has only one specific technical meaning related to Earth's rotational time.
Noun
  1. the local time at the 0 meridian passing through Greenwich, England; it is the same everywhere

Từ đồng nghĩa