*** 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
2004 Mar 28 to 2 AM on 2004 Sep 26; standard zone =   0 hrs W

For the night of: Fri, 2004 Dec 24 ---> Sat, 2004 Dec 25
Local midnight = 2004 Dec 25,    hr UT, or JD 2453364.500
Local Mean Sidereal Time at midnight =   5 03 51.8

Sunset ( 2326 m horizon):   18 29 GST; Sunrise:    7 55 GST
Evening twilight:   19 45 GST;  LMST at evening twilight:    0 48
Morning twilight:    6 38 GST;  LMST at morning twilight:   11 43
12-degr twilight:  19 16 GST -->   7 07 GST; night center:    1 12 GST

Moonrise:   16 29 GST   Moonset :    7 20 GST   
Moon at civil midnight: illuminated fraction 0.975
1.6 days until full moon, RA and dec:   4 56 21,  26 13.6

The sun is down for 13.4 hr; 10.9 hr from eve->morn 18 deg twilight.
Bright all night (moon up from evening to morning twilight).