earthtime

Contents: Description, Arguments, Usage, Examples, Sub-Functions, Related Functions, Source Supported Under Version: > 1.13 Current .dvrc Version:  Description Displays various formats of Earth time Arguments and Return Values Parameters: None input initially; the user is prompted for the parameters, one at a time Return Value: J2000 TT offset. in days (double format) Usage Syntax: earthtime() The user will initially be prompted to enter a date and time for which to calculate the time parameters. If this prompt is left blank (just hit enter), it will take the current system time. The accuracy of the outputs depends on the accuracy of the input time. If you are using the current system time, that means the outputs are only as accurate as your system clock. After requesting the date and time, the function will display, in the following order: ordinal date, local standard time, Coordinated Universal Time (UTC), International Atomic Time (TAI), TT-UTC offset (Delta-T, in seconds), Terrestrial Time (TT), Geocentric Coordinate Time (TCG), Barycentric Time offset (TB-TT, in seconds), Barycentric Time (TDB), Barycentric Coordinate Time (TCB), Julian Date (from UTC), Modified Julian Date (from UTC), Modified Julian Date (from TT), Unix time (from UTC), J2000 TT offset, and Ephemeris Time. For explanations of different time systems, see http://heasarc.gsfc.nasa.gov/docs/xte/abc/time_tutorial.html Most of the equations used in these time calculations are adapted from that NASA GSFC XTE page. Examples dv> earthtime() Time on Earth See http://heasarc.gsfc.nasa.gov/docs/xte/abc/time_tutorial.html S.Marshall 12-14-2009 First enter an Earth date and time (or leave blank for system clock) Year: Ordinal date: 2009-348 Local standard time: 18:07:31.714461 UTC-7 Coordinated Universal Time: 01:07:31.714461 UTC International Atomic Time: 01:08:05.714461 TAI TT-UTC offset (Delta-T): 66.184000 seconds Uncertainty in Delta-T: 0.000000 seconds Terrestrial Time: 01:08:37.898461 TT (a.k.a. TDT) Geocentric Coordinate Time: 01:08:38.623208 TCG Barycentric Time offset (TB-TT): 0.001631 seconds Barycentric Time: 01:08:37.900092 TB (a.k.a. TDB) Barycentric Coordinate Time: 01:08:54.0240 TCB Julian Date (UTC): 2455180.5468948 (days) Modified Julian Date (UTC): 55180.0468948 (days) Modified Julian Date (TT): 55180.0476609 (days) Unix time (UTC): 1260839251.71 (seconds) J2000 (TT) offset: 3635.5476609 days Ephemeris Time (ET): 314111317.898 (seconds) Returning J2000 TT offset... 3635.54766086182

DavinciWiki Mini-Nav Bar Contents Functions Function Categories Common Procedures Glossary Download Davinci Change Log News Mailing List Contact Developers davinci-dev [AT] mars.asu.edu All other topics See navigation on the left Major Sub-Functions atod atoi checkdate clock DeltaT double equals MJD MJD2Dt MJD2ET MJD2TT MJD2unix pause printf TB_TT time2str tzo2str Related Functions clock marstime marstimeglobal time.dvrc earthtime() Recent Library Changes Change Log Created On: 11-18-2009 Modified On: 12-15-2009