* Julian date (JD)
Days from 12:00(UT) January 1st BC4713.

* Modified Julian date (MJD)
Days from 0:00(UT) November 17, AD1858.

* Local Sidereal Time (LST)
Right ascension southing now.

* Twilight Start---Time when the sky begins to lighten End---Time when the sky becomes pitchdark

* Sun Rise---Time of sunrise Set---Time of sunset

* Moon Rise---Time of moonrise Set---Time of moonset