*** 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
1998 Mar 29 to 2 AM on 1998 Sep 27; standard zone =   0 hrs W

For the night of: Tue, 1998 May 12 ---> Wed, 1998 May 13
Local midnight = 1998 May 12, 23 hr UT, or JD 2450946.458
Local Mean Sidereal Time at midnight =  13 10 31.1

Sunset ( 2326 m horizon):   21 01 GDT; Sunrise:    7 14 GDT
Evening twilight:   22 22 GDT;  LMST at evening twilight:   11 32
Morning twilight:    5 54 GDT;  LMST at morning twilight:   19 05
12-degr twilight:  21 50 GDT -->   6 26 GDT; night center:    2 08 GDT

Moonrise:   21 40 GDT   
Moon at civil midnight: illuminated fraction 0.979
1.4 days after full moon, RA and dec:  16 27 52, -17 08.9

The sun is down for 10.2 hr;  7.5 hr from eve->morn 18 deg twilight.
Bright all night (moon up from evening to morning twilight).