1 - NGA

I
MIL-HDBK-850
to the main schema stations but am not
cxmsiderad au being part of the rrmin-sshama
Mt.l-hay kradfan uwsffw piding rnaarm for
cJlacbandtor ~ ~.
auxxrdary tkk atatton-A tide station whii
is opendad fa a short perkd of time 10 obdn
data for a *i purpose.
sasondary-1. See aecondmy grant
Gird.. 2. A cakstiil body revokhg mound
another body, its primary.
SECORA phaaa~mqwiaon efacfronis fongrsnge
dmanca-msaauring system used to
determine podiirra end OlbitS & SIXtefkke or
flight vehklea thnt contain the necasaa~
transponders. This term is an esronym for
“sequential collation of renge” (now obsofste).
section eorner~ somer at ths exlrsmify of a
section boundary,
sectlonrd charf-A series of eeronaufissl
chsris et e 1:5@3,000 scale severing W entire
United Sletes, suitable for wntasf or visual
flying.
, . ... . . ... ....“. ---- . ... . -. ,,
aaction-1. The unfr of aubdwision of a
townshp wiih tmmderies sonferming to the
mcfanoilar svetem of survevs. nominslM 1 mifs
squsre~-coni~iiig 640 acr&’s.”See also’
fractional ●octlon. 2. (leveling) That portion
ofaline ofkvals vhiihisracwdad and
abstraciad as a unit. Sae afae fractional
sactlon; half cactlon; quarter section.
mctorkl harmonke-l%e set of spherical
hermenisa wttich change fmm poaitiie to
negatiie es a furrdion of kngifuds only. Sas
alae teassral harmonics; zcmal
harmonics.
secular abarratlon-The aberralbn due to
the motien et the oentar of mesa of the solar
svsfem in smace. Also celled aberration of
ffxod strwa.
secular perturbations-Perf urbatiorrs to the
orbii of a pfanet W seleltiie that continue !0 act
in one dkasfion wifheuf limit, in crmtrast to
pariodc parturtmtimts whish cfwmgs diresfbn in
e regular msnner.
secular tarrrm-in tha mathematical
expreaakm of an orbii, terms which ara
pr’OPOIt”wal to lima, rssuffing in secular
penurbaliens.
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satactlon overf*y-A trasing of aalactad nmp
Muca *II Oorr@ad on lmrrs+mnf rrmtariel;
USW#Y d=- by the name d the Ieekuas or
ddaie depicted, such ●s contour ovartsy,
W#@#Wt SW9ffJXY.Alra cslbd tifi pUli Up;
●elonocontrlc coordinator-Oussntitias
Mich expmaa the posifbn ef a print with
raepacttothacarrferoftha Meon.
●elerrocantrlc-Rafating to tha canter d the
~ referring to the Meon es a canter. A1.aO
sallsd Iunlcentrk.
●olenodoey-@CS) Thet bmnch of appfkd
mathamatiss vhkh detarmhwe, by cbeervatien
and maaeuremant, the exact padons ef points
and the figurss and areas of large pertions of
the Man’s surfece, or !he ehapa and size of
the Moon,
aelanodetlc-(JCS) Of or pmlsining to, or
determined by, aelenodeey.
selanographic—1. Relating to the physical
geography ef tha Moon. 2. Spacifiilty,
referring to pasitions on ths Mom measured in
latitude horn the Mmn’s aquetor erxl in
bngifude from a refareme meridkm.
selano logy—That branch of astronomy that
desk with the Moon, ifs megnifufe, rnofkm,
consfifuficm, and the Iika.
solenotrope-A devise used in geodetic
surveying for reffscfing the Mcar’s mys to a
d~ant point, 10 aid in bng-diefsnsa
ebsarvations. Sea also heliotrope.
salf-lavellng fevd-A Ieval ufifiiing the actiin
of gravity in ifs operation. A prismatic cfrwiie,
called a companaator, is an integral part of
the instrument whd, ora tha imdmrrrd I’we
been roughfy leveled, causes the optical eyefem
to ewing into proper herizontel fine d sight and
to msinfain that psifion during readings at a
given statien.
saff-raadlng Iavallng rod-A rod with
greduefien marks designed fo be mad by the
ebsarvar el the Iavaiing instrument. Also sailed
speaking rod.
●elf-mgktarlng gag*Any tide or stream
gsge which providas a continuous record of the
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