Expand description
Fundamental constants for time-scale conversions, relativistic corrections, and astronomical calculations.
Constants§
- ATTOS_
DIGITS - Number of decimal digits in one attosecond-precision second (
10¹⁸). - ATTOS_
PER_ DAY - Attoseconds in one standard Earth day.
- ATTOS_
PER_ FS_ I128 - Attoseconds per femtosecond (10⁻¹⁵ s).
- ATTOS_
PER_ HALF_ DAY - Attoseconds in half a standard Earth day (12 hours).
- ATTOS_
PER_ HALF_ DAY_ U128 - Attoseconds in half a standard Earth day, as
u128. - ATTOS_
PER_ HOUR - Attoseconds in one hour.
- ATTOS_
PER_ MIN - Attoseconds in one minute.
- ATTOS_
PER_ MS_ I128 - Attoseconds per millisecond (10⁻³ s).
- ATTOS_
PER_ NS - Attoseconds per nanosecond (10⁻⁹ s).
- ATTOS_
PER_ NS_ I128 - Attoseconds per nanosecond (10⁻⁹ s).
- ATTOS_
PER_ PS_ I128 - Attoseconds per picosecond (10⁻¹² s).
- ATTOS_
PER_ SEC - Attoseconds per second.
- ATTOS_
PER_ SECF - Attoseconds per second as a floating-point value.
- ATTOS_
PER_ SEC_ I128 - Attoseconds per second as
i128. - ATTOS_
PER_ SEC_ U128 - Attoseconds per second as
u128. - ATTOS_
PER_ US_ I128 - Attoseconds per microsecond (10⁻⁶ s).
- ATTOS_
PER_ WEEK - Attoseconds in one GPS week.
- C
- Speed of light in m/s (SI definition)
- C_
SQUARED - Speed of light squared (c²) in m² s⁻².
- GM_SUN
- Solar gravitational parameter GM☉ in m³ s⁻² (nominal value from IAU 2015 Resolution B3)
- GM_
SUN_ OVER_ C3 - GM☉ / c³ in seconds (from
GM_SUNandC— used in Shapiro delay) - JD_
2000_ 2_ 451_ 545 - Julian Date of the J2000.0 epoch (JD 2451545.0).
- JD_
2000_ 2_ 451_ 545F - Julian Date of the J2000.0 epoch as a floating-point value.
- JD_
2000_ 2_ 451_ 545_ I128 - Julian Date of the J2000.0 epoch as
i128. - MJD_
1970 - Modified Julian Date of the Unix epoch (MJD 40587.0 = 1970-01-01 00:00:00 UTC).
- PLANCK_
LENGTH - Planck length ℓ_Pl in meters (standard value).
- PLANCK_
LENGTH_ 4 - Planck length to the fourth power (ℓ_Pl⁴) in m⁴.
- SEC_
PER_ DAY - Seconds in one standard Earth day (24 × 60 × 60).
- SEC_
PER_ DAY_ F - 86,400 seconds in one standard Earth day (24 hours × 60 minutes × 60 seconds).
- SEC_
PER_ DAY_ I64 - 86,400 seconds in one standard Earth day (24 hours × 60 minutes × 60 seconds).
- SEC_
PER_ HOUR - Seconds in one hour.
- SEC_
PER_ MIN - Seconds in one minute.
- SEC_
PER_ MONTH - Seconds in one average month (30.4375 days × 86_400).
- SEC_
PER_ WEEK - Seconds in one GPS week (7 days).
- SEC_
PER_ YEAR - Seconds in one Julian year (365.25 days × 86_400).
- STRTIME_
SIZE - The size limit for parsing and no-alloc formatting with the strtime related functionality.
- TAI_
ATTOS_ AT_ 1972 - Number of TAI attoseconds from noon 2000-01-01 back to midnight 1972-01-01.
- TAI_
SEC_ 1970_ MIDNIGHT_ TO_ 2000_ NOON - TAI seconds from 1970-01-01 midnight to 2000-01-01 noon.
- TT_
TAI_ OFFSET - TT–TAI offset of 32.184 s as a
Dt. - TT_
TAI_ OFFSET_ ATTOS - Fractional part of the TT–TAI offset (0.184 s) as attoseconds.
- TWO_
GM_ SUN_ OVER_ C3 - 2GM☉ / c³ — the standard prefactor in the one-way Shapiro delay formula