*** 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: Wed, 1998 May 27 ---> Thu, 1998 May 28
Local midnight = 1998 May 27, 23 hr UT, or JD 2450961.458
Local Mean Sidereal Time at midnight =  14 09 39.4

Sunset ( 2326 m horizon):   21 10 GDT; Sunrise:    7 07 GDT
Evening twilight:   22 34 GDT;  LMST at evening twilight:   12 44
Morning twilight:    5 43 GDT;  LMST at morning twilight:   19 54
12-degr twilight:  22 01 GDT -->   6 17 GDT; night center:    2 09 GDT

Moonset :   23 01 GDT   
Moon at civil midnight: illuminated fraction 0.061
2.1 days since new moon, RA and dec:   6 19 08,  18 24.0

The sun is down for  9.9 hr;  7.1 hr from eve->morn 18 deg twilight.
 6.7 dark hours after moonset and before beginning of twilight.