*** 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: Thu, 2000 May 18 ---> Fri, 2000 May 19
Local midnight = 2000 May 18, 23 hr UT, or JD 2451683.458
Local Mean Sidereal Time at midnight =  13 36 12.4

Sunset ( 2326 m horizon):   21 05 GDT; Sunrise:    7 10 GDT
Evening twilight:   22 27 GDT;  LMST at evening twilight:   12 03
Morning twilight:    5 48 GDT;  LMST at morning twilight:   19 25
12-degr twilight:  21 55 GDT -->   6 21 GDT; night center:    2 08 GDT

Moonrise:   21 07 GDT   
Moon at civil midnight: illuminated fraction 0.994
0.6 days after full moon, RA and dec:  16 19 29, -17 57.2

The sun is down for 10.1 hr;  7.3 hr from eve->morn 18 deg twilight.
Bright all night (moon up from evening to morning twilight).