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This page documents the '''planet''' function of Python module [[Analysis Utilities|analysisUtils]].
This page documents the '''planet''' function of Python module [[Analysis Utilities|analysisUtils]].


This function contacts the [http://ssd.jpl.nasa.gov/horizons.cgi#top JPL Horizons] telnet server to get the J2000 position, rate, and angular size of any Solar System body.  
This function contacts the [http://ssd.jpl.nasa.gov/horizons.cgi#top JPL Horizons] telnet server to get apparent angular size, position and rate (in the J2000 reference frame) of any Solar System body. If the date is not specified, today's date is assumed at 0:00 UT.  If the observatory is not specified, ALMA is assumed. It returns a dictionary of: {'directionRadians', 'rateRadiansPerSecond', 'angularDiameter'} where the first two elements are a list two values in radians: RA, Dec, and the third is a scalar in arc seconds.
If the date is not specified, today's date is assumed at 0:00 UT.  If the observatory is not specified, ALMA is assumed.
It returns a dictionary of: {'directionRadians', 'rateRadiansPerSecond', 'angularDiameter'} where the first two elements are a list
two values in radians: RA, Dec, and the third is a scalar in arc seconds.





Revision as of 21:42, 14 March 2012

Return to Analysis Utilities

This page documents the planet function of Python module analysisUtils.

This function contacts the JPL Horizons telnet server to get apparent angular size, position and rate (in the J2000 reference frame) of any Solar System body. If the date is not specified, today's date is assumed at 0:00 UT. If the observatory is not specified, ALMA is assumed. It returns a dictionary of: {'directionRadians', 'rateRadiansPerSecond', 'angularDiameter'} where the first two elements are a list two values in radians: RA, Dec, and the third is a scalar in arc seconds.


Usage

Usage: au.planet(solarSystemBody="", date="", observatory='ALMA', verbose=False)
The format of the date string is: '2011-10-31 11:59:59' or simply '2011-10-31' for 0 UT
Observatories can be specified by JPL ID string, JPL ID integer, or by the following names:

 * 'VLA' (which will be converted to = '-5')
 * 'ALMA' (which will be converted to = '-7')
 * 'MAUNAKEA' (which will be converted to = '-80')
 * 'OVRO' (which will be converted to = '-81')

Examples

CASA <7>: au.planet('Titan','2012-04-01','EVLA')
Using observatory: VLA = -5
Assuming 0 hours UT
MJD= 56018.00000, MJDseconds = 4839955200.0
Confirmed Observatory name =  VLA
Confirmed Target ID = 606 = Titan
J2000 Position: 13:44:49.19, -007:52:27.645, rate: -11.9723, 3.3884 arcsec/hr
Angular diameter = 0.811703 arcsec
  Out[7]:
{'angularDiameter': 0.81170299999999995,
 'directionRadians': [3.5989557494879238, -0.13743326065058692],
 'rateRadiansPerSecond': [-1.6123152317632495e-08, 4.5631673694531841e-09]}

CASA <10>: au.planet('Moon','2012-04-01 12:55')
MJD= 56018.53819, MJDseconds = 4840001700.0
Confirmed Observatory name =  ALMA
Confirmed Target ID = 301 = Moon
J2000 Position: 08:14:33.97, +015:40:16.537, rate: 2648.9190, -473.5570 arcsec/hr
Angular diameter = 1831.355000 arcsec
  Out[10]:
{'angularDiameter': 1831.355,
 'directionRadians': [2.1579522287809869, 0.27351509191740353],
 'rateRadiansPerSecond': [3.5673115870860856e-06, -6.3774142329219044e-07]}