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Reference frames
Explore 30 published pages about reference frames. Choose a topic below, then follow its sources, explanations, and applications.
Each article describes its own sources and limits. This page organizes the collection for reading.
Articles and guides
- Apparent and mean position
- Atmospheric refraction
- Ayanamsa selection
- Birth time uncertainty
- Calendar conversion
- Civil twilight
- Coordinate precision
- Daylight saving transitions
- Delta t
- East west longitude sign
- Ecliptic and equatorial coordinates
- Ephemeris version
- Geocentric and topocentric positions
- Gregorian and julian calendar boundary
- Historical time zones
- Julian day
- Leap seconds
- Light time correction
- Local sidereal time
- Missing location inputs
- Nutation
- Observer latitude and longitude
- Polar latitudes
- Precession
- Rise and set conventions
- Stellar aberration
- Tropical and sidereal zodiacs
- True and mean lunar node
- Utc and local time
- Whole sign and quadrant houses