1 - NGA

Srdtqaad dtiddcurrmfs.tand tohcmeaaaa
he Moon apfmnrchaa perigee and 10 dac$fase
Saifqmmchas apogee.
pmslhx-1. (JCS) In photography. the
~rant di+lecemer$ of the poaitiin of m
object m ralstii to a rdarenca point due to a
change m the point of observation. 2. The
appararrf d~lacemant bafwwan objacfs on the
Earth’s surfaca due to thaii diiemnca in
elevation. Also called ●ngufar parallax; want
of corr~spondmrco. Sea also ●bsoluto
●tarooaoopic parallax; sga of parallax
Inequality; ●nnual parallsx; ●quatorid
horlzontd parallax: ?deo parallax;
goocentrlc p~rdlax; horizontal parallax;
Inatrurrmnt parallax; lunar parallax;
raaldusrl parallax solar parallax; yparallax.
parallel of attftude-A circle of the calestisl
sphere pamllel to the horizerr cmnacting all
points of aqual attiiude. AISAJcalled
dmucantrtr; dtltuda circle; circle of
●qual dtltuda.
pamllel of decfinatlon-A circte of the
celest’ml sphere parallel to ths cslastial equator.
Also cslled celastlal parallel; circle of
equsl docftnatlon.
parallel of latltude-See drda of
Iongltudo.
parallel plate-An optical disk with optically
fist, frarattsl tmrfa~ used aspacielly in epticd
micmmeters. Atso called pfene plate. See
also optical ffat.
pamllel sphere-The celestiel sphere as it
appaers 10 an observer at the pole, where
cdeetial bodias -r to nxwa psrallal to ths
horizon.
parallal-A circle on the surface of the Earth,
parallel 10 tha pfane of the Equator and
contracting all points of equsl Letitude, or a circla
paeltel to the primery grast circle d a sphere or
sphamid; also, a closed cwve approxinmling
such a circla. Also callad Inverao oarallal.
Sae al- ●stronomic parallal; tillptlc
parallal;
parallel:
parallel;
parallel:
parallal:
pamllal;
flctltloua parallal: gaodatic
goographlc paralld: grid
ground parallel; Iaomatrlc
oblique parallal; photograph
prlnclpal parallal; standard
tranaveraa parallal.
MI L-HDBK-850
paramoterlxa-l%e act or process of
deMX?MIg a geornatric ailustim with a
rmlhamstical model canteining edjuetabla
mtsants.
paramatar—in general, any qusntify of a
pmtrfam that is nd an hrrfaparrderrt variable.
More apacifiilly ths term Lsoften ussd to
dstinguhh from dependent variables quantifies
tiih msy be as@nad arbkrary vahmw for
P@~s of tfv? problem a! fmnrt.
pammatrlc ●quatlOne-A eat of aquatiins in
which the independent varisfias or cxmrdirAes
are aach axprti in terms d a paramsfer.
parametric krtltuds-l%e angle at the @ntar
of a a@em whiih is tangent to the aU@soid
along the gsodetic equator, betwean the pfane
of the equator and the mdlua to the pdrtf
intersected on the sphere by a straight line
perpandiiulsr to the plane of the Equator and
passing through the pdnt on the ellipsoid whose
parametric falitude is defiisd. Parametric
Islituda is an ausiliafy tstitude used in problems
of geodesy and cartography.
paraxlal my—A ray whoaa psth lies very nasr
the axis of a lens and whiih intersects the lens
surface et e point very cioss to its vertex end at
nearly normsl incidence,
partial tlds-%s conetltuent.
pasa point-A point whose horizontal atior
varrioel position is dsterminad from phorogmphs
by photogmmmetric methods and whiih Is
intended for use in the abadute orientation of e
medel. Also cdlsd photogrammetrlc pcdnt.
See also annex point; supplemental
elevation; ●upplamontal position.
paaelva aatelllte-A selellhe” which contakrs
no pver syces 10 sugmen! output POwen a
setelhte wfwch is a pessive raflsctor. Sea also
■ctive satalllta.
paaa-1. A single circuil c4 the Earth by a
satelliie. See also orbit 2. The period of time
a sstelliie is wiihin telemetry range d a deta
acquisition stat”kxr. 3. (rnansuretion) Orre
COmpl?t? -t of pointings or maasuramants on
a sp~~lc Plate, reeeau, or other rn.adii
contammg photograph~ imagery.
patch-(digital) A small ares d irrformetii
eplii into a data base or eofiwere in otdar to
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