Triple

Given a phrase, classify it is english named entity (e.g., persons, organizations, works of art) in Latin script, or not (e.g., literals, dates, URLs, verbose phrases). For disambiguation, the statement where the phrase occurs as object is also given. Please return a JSON object with `phrase` (string, the phrase being analyzed) and `is_ne` (boolean, indicating whether the phrase is a Named Entity).

Phrase: IAU 1976 system of astronomical constants | Statement: [Barycentric Dynamical Time, definedIn, IAU 1976 system of astronomical constants]

Target entity: IAU 1976 system of astronomical constants
Context triple: [Barycentric Dynamical Time, definedIn, IAU 1976 system of astronomical constants]

• A. International Celestial Reference System
  The International Celestial Reference System is the standard, high-precision coordinate framework used in astronomy and geodesy to define positions of celestial objects relative to distant quasars.
• B. IERS Conventions
  IERS Conventions are a set of internationally recognized technical standards and models that define how to precisely measure and reference Earth’s rotation, orientation, and reference frames for geodesy and astronomy.
• C. Barycentric Celestial Reference System
  The Barycentric Celestial Reference System is a relativistic, solar-system–centered coordinate framework used in astronomy and astrometry to precisely describe the positions and motions of celestial bodies with respect to the solar system’s center of mass.
• D. IERS Bulletin A
  IERS Bulletin A is a regularly issued publication by the International Earth Rotation and Reference Systems Service that provides rapid updates and predictions of Earth orientation parameters and time scale differences such as UT1–UTC.
• E. A Catalogue of 838 Principal Fixed Stars
  A Catalogue of 838 Principal Fixed Stars is an influential 19th-century astronomical star catalog compiled by Francis Baily that systematically lists and refines the positions of key stars for observational and navigational use.
• F. None of above. chosen
• G. Unsure - the case is ambiguous/there is not enough information to decide.

Generate a one-sentence description of the target entity. 
You are given a context triple in the form (subject, predicate, object), where the object is the target entity. 
# Instructions
Use the triple to infer relevant information about the entity. Describe the entity based on what is most defining, well-known. 
Avoid repeating the information from the triple, unless really essential.
# Response Format
Return only the sentence: "Description: [one-sentence description of the target entity]"

Entity: IAU 1976 system of astronomical constants
Triple: [Barycentric Dynamical Time, definedIn, IAU 1976 system of astronomical constants]

The IAU 1976 system of astronomical constants is a standardized set of numerical values and definitions adopted by the International Astronomical Union to ensure consistency in celestial mechanics, timekeeping, and other astronomical calculations.

Target entity: IAU 1976 system of astronomical constants
Target entity description: The IAU 1976 system of astronomical constants is a standardized set of numerical values and definitions adopted by the International Astronomical Union to ensure consistency in celestial mechanics, timekeeping, and other astronomical calculations.

• A. International Celestial Reference System
  The International Celestial Reference System is the standard, high-precision coordinate framework used in astronomy and geodesy to define positions of celestial objects relative to distant quasars.
• B. IERS Conventions
  IERS Conventions are a set of internationally recognized technical standards and models that define how to precisely measure and reference Earth’s rotation, orientation, and reference frames for geodesy and astronomy.
• C. Barycentric Celestial Reference System
  The Barycentric Celestial Reference System is a relativistic, solar-system–centered coordinate framework used in astronomy and astrometry to precisely describe the positions and motions of celestial bodies with respect to the solar system’s center of mass.
• D. IERS Bulletin A
  IERS Bulletin A is a regularly issued publication by the International Earth Rotation and Reference Systems Service that provides rapid updates and predictions of Earth orientation parameters and time scale differences such as UT1–UTC.
• E. A Catalogue of 838 Principal Fixed Stars
  A Catalogue of 838 Principal Fixed Stars is an influential 19th-century astronomical star catalog compiled by Francis Baily that systematically lists and refines the positions of key stars for observational and navigational use.
• F. None of above. chosen