WinJUPOS software

WinJUPOS 12.3.9  released on 2024 May 13
WinJUPOS 12.3.5  released on 2024 March 15

Please note: WinJUPOS 10.2.0 and later use another definition of System 3 which was already implemented in the DOS predecessor PC-JUPOS. Master data (MEA and CMT), Selections (WSE) and Positional averages (PAV) are unaffected by this change. However, you have to re-generate, e.g., Drift charts in order to re-calculate System 3!

PC-JUPOS <= 6.24   ...   870.536°/d   ...  [2]
PC-JUPOS >= 6.30; WinJUPOS <= 10.1.15   ...   870.5366420°/d   ...  [3]
WinJUPOS >= 10.2.0   ...   870.536°/d   ...  [8]

[2] Seidelmann, P. K.: Explanatory Supplement to The Astronomical Almanac, University Science Book, Mill Valley (California), 1992
[3] P. K. Seidelmann (Chair), B. A. Archinal (Vice-Chair), M. F. A'Hearn, D. P. Cruikshank, J. L. Hilton, H. U. Keller, J. Oberst, J. L. Simon, P. Stooke, D. J. Tholen, and P. C. Thomas, Report Of The IAU/IAG Working Group On Cartographic Coordinates And Rotational Elements: 2003, Celestial Mechanics and Dynamical Astronomy, 2005, 91, pp. 203-215,
[8] B. A. Archinal, M. F. A'Hearn, E. Bowell, A. Conrad, G. J. Consolmagno, R. Courtin, T. Fukushima, D. Hestroffer, J. L. Hilton, G. A. Krasinsky, G. Neumann, J. Oberst, P. K. Seidelmann, P. Stooke, D. J. Tholen,P. C. Thomas, I. P. Williams. , Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2009, Celestial Mechanics and Dynamical Astronomy, 2011, Volume 109, Issue 2, pp 101-135,

See also here.

You may find newer, though perhaps not yet widely tested versions and a changelog on Grischa's website.

Features of WinJUPOS are documented in its built-in F1 help, and summarized on Grischa's Introduction page.

For a list of external tutorials written by WinJUPOS users and compiled by Grischa click here.

Please note: Longitudes of Jupiter's Central Meridian calculated by WinJUPOS and its predecessor PC-JUPOS always refer to the illuminated disk (i.e., they are phase-corrected), not the full planet's ellipse as done by most other ephemerides. The difference between both types of Central Meridians can reach 0.6° maximum. This divergence affects longitudes of Central Meridians only, and has no impact on object longitudes measured on images.


To visit the main page of the JUPOS project, go to or