Video: Time

Time

What is Time: BJD

Barycentric Julian Day (BJD) time is the universal day and time at the center of the solar system and is crucial to many astronomically-relevant processes as well as other time scales.

Time

What is an Ephemeris

A highly useful concept for applications in both Double and Variable Stars, an Ephemeris is an estimation of where/when a particular astronomical event will occur at a particular time in the future.

Time

What is Time: HJD

Heliocentric Julian Date (HJD) is the Julian Date corrected for the differences in the Earth’s position relative to the center of the Sun.

Time

What is Time: JD

Julian Dates (JD) are a continuous count of days, and fractions of days, since noon Universal Time on January 1, 4713 BC (on the Julian calendar)

Time

What is an Epoch

An epoch is a particular time period, point in history, or a moment defined by a particular event, and is a moment of time used as a reference point for a time-varying astronomical quantity.