ephemeris-time
Ads
Free Ephemeris www.ask.com/Free+Ephemeris Explore Free Ephemeris. Get Answers Now on Ask.com.
Dictionary.com Mobile www.dictionary.com/mobile Join 45 Million Happy Mobile Users Today On Our Award-Winning Four Star App. Download Now!
ephemeris time
noun Astronomy.
time measured by the orbital movements of the earth, the moon, and the planets.
Origin:
1945–50
1945–50
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2013.
Cite This Source
Based on the Random House Dictionary, © Random House, Inc. 2013.
Cite This Source
|
Link To ephemeris-time
Collins
World English Dictionary
| ephemeris time | |
| —n | |
| time that is based on the orbit of the earth around the sun rather than the axial rotation of the earth, one ephemeris second being 1/31 556 925.9747 of the tropical year 1900. It was used from 1960 to 1983 as an astronomical timescale but has been replaced by terrestrial dynamical time and barycentric dynamic time | |
Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
00:10
Ephemeris-time
is always a great word to know.
So is interrobang. Does it mean:
| a scrap or morsel of food left at a meal. |
| a printed punctuation mark (‽), available only in some typefaces, designed to combine the question mark (?) and the exclamation point (!), indicating a mixture of query and interjection, as after a rhetorical question. |
American Heritage
Science Dictionary
| ephemeris time
A highly accurate astronomical system for the measurement of time based in theory on the period of Earth's orbit, but in practice relying on lunar observations and an accurate lunar ephemeris so as to not be subject to the irregularities of Earth's rotation. The year 1900 CE is considered a standard year, containing 31,556,925.9747 seconds of ephemeris time. |
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
Nearby Words
Copyright © 2013 Dictionary.com, LLC. All rights reserved.
