next »

[eV1Te]

I extracted the coordinates of Pioneer 11 in 1979-08-31 from the NASA Horizon tool. (http://ssd.jpl.nasa.gov/?horizons).

Pioneer 11 passed extremely close to Saturn, actually on the inside/trough the rings.


(Place the Horizon file in your Data folder and the Pioneer file in your Systems folder)

ftp://universe:sandbox@ev1te.myftp.org/universe/Pioneer_11_Horizon.zip

[Dan Dixon]

Very awesome; excellent work. I'll be including this system in the next release of Universe Sandbox.


And now the caveats (both of which are my fault):

1 - Files placed under the installation folder may be deleted when there's a new update and so all user created systems should be saved in 'My Documents\Universe Sandbox\Systems'. The updater will never delete anything in saved in My Documents.

eV1Te rather awesomely created this system with its own Horizon-yyyy-mm-dd.xml file but to make this work you must put it in the Data folder which is in the installation folder (which may be deleted once there's an update).

So in the next release I'll add support for reading these 'Horizon' files from My Documents.

2 - Saturn's axis may not be lined up correctly with the moons. Currently Universe Sandbox looks for a particular moon (Daphnis for Saturn) that wasn't included in this system and uses its velocity information as the plane to use for the rings. I'll be adding code to search for more common moons in the next release (which will change the angle of the rings in this system to be more correct).

[eV1Te]

Thanks for the great response!

At the moment I am making simulations of all the major gravity assists done by for example Voyager I & II. I find it more convenient to use the concept of creating one Horizon file for one date then only create one simple system file which only includes date (which corresponds to the horizon file) and the wanted bodies. (Thanks Dan for updating the compability with that kind of files in future releases)

The bodies I am extracting from the Horizon database is all the planets with there corresponding major moons which is only the 4 largest of Jupiter, an 5 largest of Saturn for example, partially because all the moons was not discovered at that time plus the interesting man made space satellites at that time. (Is there some interest of extracting more bodies?)

I'll keep you updated Dan..