Arnold Colina 2025-10-16 UPDATE U.S. Naval Observatory Time Service USN8 40451S009 TRIANGULATED AL STRUTS 7.0 ROOF MOUNTING BRACKET HOLE, ARP 2014-11-12T16:00:00Z on aluminum structure on roof of of 2-story Same DOMES number as USN7 since same antenna The antenna is mounted on a baseball diamond shaped aluminum structure mounted on the roof (2 stories) of the Time Service department building at the U.S. Naval Observatory, Washington. D.C.. There are nearby geodetic markers, but this antenna has not been surveyed to those markers. (see accompanying pictures). USN7 functionally replaces USN3. The antenna mount was extended by 1.5m on 2014-11-12. Washington D.C. United States of America (the) NORTH AMERICAN 1112162.138 -4842854.667 3985497.066 38.9205661139 -77.0662765972 Same DOMES number as USN7 since same antenna The antenna is mounted on a baseball diamond shaped aluminum structure mounted on the roof (2 stories) of the Time Service department building at the U.S. Naval Observatory, Washington. D.C.. There are nearby geodetic markers, but this antenna has not been surveyed to those markers. (see accompanying pictures). USN7 functionally replaces USN3. The antenna mount was extended by 1.5m on 2014-11-12. SN11203000923 SEPT POLARX4TR GPS+GLO+GAL+SBAS 2.3.4 0 2014-11-12T11:00:00Z 2015-01-22T20:08:00Z 2014-11-12T00:00:00Z SN11203000923 SEPT POLARX4TR GPS+GLO+GAL+SBAS 2.5.2 0 2015-01-22T20:34:00Z 2018-07-09T14:40:00Z 2015-01-22T00:00:00Z SN11203000923 SEPT POLARX4TR GPS+GLO+GAL+SBAS 2.9.6 0 2018-07-09T14:40:00Z 2019-03-19T18:25:00Z 2018-07-09T00:00:00Z 4701171 SEPT POLARX5TR GPS+GLO+GAL+BDS+SBAS 5.0.3 0 2019-03-25T15:06:00Z 2019-04-03T07:50:00Z 2019-03-25T00:00:00Z 4701171 SEPT POLARX5TR GPS+GLO+GAL+BDS+SBAS 5.2.0 0 2019-04-03T07:50:00Z 2024-07-30T00:00:00Z 2019-04-03T00:00:00Z 4701171 SEPT POLARX5TR GPS+GLO+GAL+BDS+SBAS 5.5.0 0 2024-07-30T00:00:00Z 2024-08-22T15:08:18Z 762-11615 TPSCR.G5 TPSH BPA 0.0000 0.0000 0.0000 0 TPSH Andrew FSJ1-50A (35422-33 phase stabilized) 39 2014-11-12T11:00:00Z 2014-11-12T00:00:00Z EXTERNAL H-MASER 10.0 1998-03-24 Reference signal from USNO Master clock (MC2), the primary realization of UTC(USNO), located in Bldg. 78 in a thermal chamber. MC2 is steered to UTC using information obtained from the Bureau International des Poids et Mesures (BIPM) roughly each month. See the BIPM Circular T for more detail, http://www.bipm.fr/enus/5_Scientific/c_time/ time_ftp.shtml 1998-03-24T00:00:00Z GPS PERMANENT 2015-01-22 2015-01-22T00:00:00Z HUMICA H-sensor (pn 16663) NOAA GSOS # 062 Vaisala -0.724 2001-08-21 15 1 NATURAL 2001-08-21T00:00:00Z PTB220 met sensors are located at USNO on rooftop of Building 52A (~ few hundred m from GPS ant.) NOAA GSOS # 062 Vaisala -0.724 2001-08-21 15 0.1 2001-08-21T00:00:00Z PT100 RTD 1/s DIN 43760B NOAA GSOS # 062 Vaisala -0.724 2001-08-21 15 0.1 NATURAL 2001-08-21T00:00:00Z John Adams US Naval Observatory +1 (202) 762-0740 3450 Massachusetts Ave. NW Washington, DC 20392 gnss@us.navy.mil Arnold Colina US Naval Observatory +1 (202) 762-1455 3450 Massachusetts Ave. NW Washington, DC 20392 gnss@us.navy.mil Arnold Colina U.S. Naval Observatory 202-762-1455 Precise Time Department 3450 Massachusetts Ave., NW Washington, D.C. 20392-5420 gnss@us.navy.mil John Adams U.S. Naval Observatory 202-762-0740 Precise Time Department 3450 Massachusetts Ave., NW Washington, D.C. 20392-5420 gnss@us.navy.mil CDDIS IGN N N N no monument N TODO USN8_1.jpg image 2014-01-01T00:01:27Z 2023-03-01T00:00:00Z USN8_2.jpg image 2014-01-01T00:02:05Z 2023-03-02T00:00:00Z USN8_3.jpg image 2014-01-01T00:11:37Z 2023-03-03T00:00:00Z USN8_4.jpg image 2014-01-01T00:19:12Z 2023-03-04T00:00:00Z