View Source SpaceDust.Time.TT (Space Dust v0.3.0)

Terrestrial Time (TT).

TT is the modern astronomical time standard for geocentric ephemerides. It provides a uniform time scale for planetary and lunar ephemeris calculations.

TT = TAI + 32.184 seconds

The 32.184 second offset was chosen to maintain continuity with the older Ephemeris Time (ET) standard at the time of the transition.

Internally stores time as fractional seconds since a TT reference epoch.

Summary

Types

t()

Functions

add(tt, seconds)

Add seconds to TT time.

diff(tt1, tt2)

Difference between two TT times in seconds.

from_jd(jd)

Create TT from Julian Date (in TT scale).

from_tensor(tensor)

Create from Nx tensor.

julian_centuries_j2000(tt)

Calculate Julian centuries since J2000.0 in TT. This is commonly used for precession/nutation calculations.

new(tt_seconds)

Create a TT time from TT seconds.

to_jd(tt)

Convert TT to Julian Date.

to_seconds(tt)

Get the TT seconds value.

to_tensor(tt)

Convert to Nx tensor.

Types

t()

@type t() :: %SpaceDust.Time.TT{tt_seconds: float()}

Functions

add(tt, seconds)

@spec add(t(), number()) :: t()

Add seconds to TT time.

diff(tt1, tt2)

@spec diff(t(), t()) :: float()

Difference between two TT times in seconds.

from_jd(jd)

@spec from_jd(float()) :: t()

Create TT from Julian Date (in TT scale).

from_tensor(tensor)

@spec from_tensor(Nx.Tensor.t()) :: t()

Create from Nx tensor.

julian_centuries_j2000(tt)

@spec julian_centuries_j2000(t()) :: float()

Calculate Julian centuries since J2000.0 in TT. This is commonly used for precession/nutation calculations.

new(tt_seconds)

@spec new(float()) :: t()

Create a TT time from TT seconds.

to_jd(tt)

@spec to_jd(t()) :: float()

Convert TT to Julian Date.

to_seconds(tt)

@spec to_seconds(t()) :: float()

Get the TT seconds value.

to_tensor(tt)

@spec to_tensor(t()) :: Nx.Tensor.t()

Convert to Nx tensor.