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commenthol / astronomia

An astronomical library
MIT License
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How to find apparent ra/dec of planets(such as mars, jupiter)? #22

Open hjy1210 opened 3 years ago

hjy1210 commented 3 years ago

Form HORIZONS Web-Interface, use settings:

Ephemeris Type [change] : | OBSERVER
Target Body [change] : | Mars [499]
Observer Location [change] : | Geocentric [500]
Time Span [change] : | Start=2021-1-1, Stop=2021-1-2, Intervals=1
Table Settings [change] : | QUANTITIES=1,2,20; angle format=DEG
Display/Output [change] : | default (formatted HTML)

I can find mars location at 2021/1/1 0:0:0 UTC as follow:

**************************************************************************************************
 Date__(UT)__HR:MN:SC.fff     R.A.___(ICRF)___DEC R.A._(a-appar)_DEC.            delta      deldot
**************************************************************************************************
$$SOE
 2021-Jan-01 00:00:00.000      24.79948  11.23957  25.07558  11.34477 0.89856820833498  15.6579710
 2021-Jan-02 00:00:00.000      25.20526  11.41417  25.48167  11.51905 0.90763028296333  15.7216113
$$EOE
**************************************************************************************************

How can we use astronomia package to get such data with reasonal precision?

mdmunir commented 3 years ago

https://github.com/commenthol/astronomia/blob/master/src/elliptic.js#L29