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Time Commands

Time system conversions and calculations.

Commands​

starward time now​

Display current time in multiple formats.

starward time now

Output includes UTC, Julian Date, Modified Julian Date, and Unix timestamp.

starward time convert​

Convert between time formats.

# From Julian Date
starward time convert 2451545.0

# From ISO date
starward time convert "2000-01-01T12:00:00"

# From Unix timestamp
starward time convert 946728000

starward time jd​

Get Julian Date for a specific time.

starward time jd "2024-06-21 12:00:00"

Time Systems​

SystemDescription
JDJulian Date — days since Jan 1, 4713 BC
MJDModified JD — JD minus 2400000.5
UnixSeconds since Jan 1, 1970
LSTLocal Sidereal Time

Examples​

# Current time with verbose calculation
starward time now --verbose

# JSON output for scripting
starward time now --json

# Convert J2000.0 epoch
starward time convert 2451545.0

Python API​

from starward import JulianDate, jd_now, utc_to_jd

# Current time
now = jd_now()
print(f"JD: {now.jd}")

# Convert from datetime
from datetime import datetime
jd = utc_to_jd(datetime(2024, 6, 21, 12, 0, 0))

# Access properties
print(f"T (centuries since J2000): {jd.t_j2000}")