*** Almanac for the currently specified date ***:
Almanac for Roque de los Muchachos:
long.   1 11 31 (h.m.s) W, lat.  28 45.5 (d.m), elev.  2326 m
pseudo-Greenwich Daylight Savings Time assumed from 2 AM on
2000 Mar 26 to 2 AM on 2000 Sep 24; standard zone =   0 hrs W

For the night of: Mon, 2000 May 22 ---> Tue, 2000 May 23
Local midnight = 2000 May 22, 23 hr UT, or JD 2451687.458
Local Mean Sidereal Time at midnight =  13 51 58.6

Sunset ( 2326 m horizon):   21 08 GDT; Sunrise:    7 09 GDT
Evening twilight:   22 31 GDT;  LMST at evening twilight:   12 22
Morning twilight:    5 46 GDT;  LMST at morning twilight:   19 38
12-degr twilight:  21 58 GDT -->   6 19 GDT; night center:    2 08 GDT

Moonrise:    0 30 GDT   
Moon at civil midnight: illuminated fraction 0.810
3.5 days before last quarter, RA and dec:  19 43 03, -21 38.2

The sun is down for 10.0 hr;  7.2 hr from eve->morn 18 deg twilight.
 2.0 dark hours after end of twilight and before moonrise.