Csillagváros.Hu

Bug Description

Imported 2012 DA14 using MPC importer. It places it in the wrong place in the sky compared with the positions reported by MPC and JPL Horizons - all using the same site. I was looking at its closest approach (on 15 Feb 2013), using Kielder Observatory as the site. The values for Az/El, RA/Dec and distance are all wrong. I checked that the values in the ssytem.ini file matched those on MPC site.

Error may be becuase DA14 gets so close (~36,000 km), as results are much more accurate for slightly more distant Solar System objects I have added (e.g. comets ISON & PanStarrs).

Nick Fedoseev (nick-ut2uz) wrote on 2013-01-28: #1
2012 DA14 position error for 2013/Feb/15 19:30Edit (78.9 KiB, image/jpeg)

The problem is due to fast orbit elements change near any big planet.

Let me describe the problem in details by example with above mentioned 2012 DA14.
If JPL Horizons orbit data for 2013/Feb/15 19:30:00 orbit_Epoch is used in ssystem.ini, then Stellarium shows correct position for 2013/Feb/15 19:30:00 +- couple of minutes. Then the position error increases.

So, a set of records for 2012 DA14 was created for different orbit_Epoch values using JPL Horizons. For convenince, those records were named "19:00", "19:15" etc. indicating orbit_Epoch value.

Attached picture shows the result for 2013/Feb/15 19:30:00.

Seems that orbit elements should be updated from the internet or local source, automatically or by a keypress. Current solution with frequent updating ssystem.ini with according Stellarium restart seems to be not a very good idea.

Tudom hogy nem sokan használnák