CHE SIGNIFICA EPHEMERIS TIME IN INGLESE
Ephemeris tempo
Il termine termine ephemeris (spesso abbreviato ET) può in linea di principio riferirsi al tempo in connessione con qualsiasi ephemeris astronomica. In pratica è stato utilizzato in modo più specifico per riferirsi a: ▪ un'ora scala temporale standard astronomica adottata nel 1952 dall'IAU e sostituita negli anni '70. Questa scala temporale è stata proposta nel 1948, per superare gli inconvenienti di tempo solare medio irregolarmente fluttuante. L'intento era quello di definire un tempo uniforme (per quanto fosse possibile) basato sulla teoria newtoniana (cfr. Qui di seguito: Definizione dell'ephemerismo (1952)). L'ephemeris era una prima applicazione del concetto di una scala temporale dinamica, in cui la scala temporale e temporale sono definiti implicitamente, dedotti dalla posizione osservata di un oggetto astronomico attraverso la teoria dinamica del suo moto. ▪ una moderna scala temporale di coordinate relativistiche, attuata dall'argomento dell'ephemeris JPL, Teph, in una serie di Ephemeridi di sviluppo integrati numericamente. Tra di essi sono le efemere DE405 in uso corrente diffuso.
definizione di ephemeris time nel dizionario inglese
La definizione del tempo delle effemeridi nel dizionario è il tempo che si basa sull'orbita della terra intorno al sole piuttosto che sulla rotazione assiale della terra, una seconda delle effemeridi è 1/31 556 925.9747 dell'anno tropicale del 1900. È stata utilizzata da 1960-1983 come una scala cronologica astronomica, ma è stata sostituita dal tempo dinamico terrestre e dal tempo dinamico baricentrico.
PAROLE IN INGLESE ASSOCIATE CON «EPHEMERIS TIME»
ephemeris time ·
ephemeris ·
time ·
term ·
often ·
abbreviated ·
principle ·
refer ·
connection ·
with ·
astronomical ·
practice ·
been ·
used ·
more ·
specifically ·
former ·
standard ·
scale ·
adopted ·
superseded ·
this ·
proposed ·
overcome ·
drawbacks ·
irregularly ·
fluctuating ·
mean ·
solar ·
intent ·
chronology ·
encyclopedia ·
britannica ·
history ·
international ·
union ·
highly ·
accurate ·
system ·
measurement ·
period ·
earth ·
orbit ·
relying ·
lunar ·
observations ·
measured ·
orbital ·
movements ·
moon ·
planets ·
noun ·
uncountable ·
astronomy ·
intended ·
infoplease ·
motions ·
does ·
rotate ·
speed ·
nasa ·
eclipse ·
site ·
introduced ·
address ·
problem ·
second ·
merriam ·
webster ·
measure ·
known ·
learn ·
about ·
vocabulary ·
terrestrial ·
corrected ·
irregularities ·
atomic ·
systems ·
kaye ·
laby ·
order ·
maintain ·
continuity ·
timescale ·
many ·
theories ·
provides ·
oxford ·
dictionaries ·
when ·
become ·
relevant ·
questions ·
general ·
indications ·
over ·
long ·
periods ·
wish ·
look ·
beyond ·
reference ·
ways ·
inconvenient ·
replaced ·
wiktionary ·
jump ·
navigation ·
search ·
edit ·
article ·
eric ·
10 LIBRI IN INGLESE ASSOCIATI CON «EPHEMERIS TIME»
Scopri l'uso di
ephemeris time nella seguente selezione bibliografica. Libri associati con
ephemeris time e piccoli estratti per contestualizzare il loro uso nella letteratura.
1
Practical Astronomy with Your Calculator
16 Ephemeris time (ET) and terrestrial dynamic time (11)1) Universal and
sidereal time are both tied directly to the period of the rotation of the Earth about
its polar axis. The Earth is being used in effect as the balance-wheel of a cosmic
clock ...
Peter Duffett-Smith,
1988
2
Glossary of Mapping Science
(2) The meridian where the Greenwich mean astronomical meridian would have
been if the Earth had rotated uniformly at the rate implicit in the definition of
ephemeris time. It is located at 1 .002738 T east of the actual meridian of
Greenwich ...
American Society of Civil Engineers,
1994
3
Time: From Earth Rotation to Atomic Physics
further more accurate observations of the motions of solar system bodies would
lead to improvements of the ephemerides and a resulting change in the
realizations of ephemeris time. Beside these technical problems with the
definition and ...
Dennis D. McCarthy, Kenneth P. Seidelmann,
2009
4
Astronomy on the Personal Computer
Since 1 984, dynamical time has replaced Ephemeris Time ( ET). The basis on
which the latter had previously been established was that of tables of the motion
of the Sun, the Moon, and the planets, which had been calculated according to ...
5.1.1 Ephemeris Time Ephemeris Time was adopted in 19602 to cope with
irregularities in the Earth's rotation that had been found to affect the flow of mean
solar time. Even though its definition is based on Newtonian physics and has ...
Oliver Montenbruck, Eberhard Gill,
2000
6
Orbital Motion, Fourth Edition
2.11.4 Ephemeris Time Both mean solar time and sidereal time are based on the
rotation of the Earth on its axis. Until comparatively recently it was thought that,
apart from a slow secular increase in the rotation period due to tidal friction, the ...
7
Time, the Familiar Stranger
The same Circular D also carries corrections to international atomic time (see
below), coordinates of the earth's pole in terms of ephemeris time, and the
lengths of past days. For instance, September 10, 1986, was 86,400.00125
seconds long, ...
Julius Thomas Fraser,
1987
8
Philosophy and the Foundations of Dynamics
The trick is to use “ephemeris time.” One builds a theoretical model that takes into
account the observed motions of the celestial bodies relative to the “fixed stars”
and their mutual gravitational interactions, using the best series approximations ...
9
Explanatory Supplement to the Astronomical Almanac
Since Newcomb's tables were the basis of the fundamental ephemerides of the
inner planets, the independent variable of his tables was called ephemeris time (
ET). It became associated with the concept of a uniform measure of time, based ...
P. Kenneth Seidelmann,
2006
10
Sky and Ocean Joined: The U. S. Naval Observatory 1830-2000
At that time Ephemeris Time and Universal Time agreed; both were o h, o min,
o s at the same instant. Soon other atomic-time laboratories joined this time scale
. However, having an atomic time scale was not the same as using that time scale
...
NOTIZIE DOVE SI INCLUDE IL TERMINE «EPHEMERIS TIME»
Vedi di che si parla nei media nazionali e internazionali e come viene utilizzato il termine ino
ephemeris time nel contesto delle seguenti notizie.
Spring ephemeral wildflowers: Our first forest natives
On a grander scale, astronomers have ephemeris time, a uniform measure defined by planetary orbital motions. But closer to home in our ... «Peninsula Gateway, mar 15»