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[UX Issue] Why Does My Simulation Of Jupiter Not Orbit Around The Sun As Expected? (Answer: Choose A Fixed Position In Space)

My program Starry Night Pro8 is not working correctly

and I have NO response, help, corrections, suggestions from

the software providers. I click backwards from todays date 26 24-lhour

earth days and Jupiter goes in its "normal" counter clockwise orbit (should

be clockwise) and does a COMPLETE orbit in 26 earth days. Its actuall orbit

is 4,332.59 earth days. Dave Whipps has interacted but since he has a different

software (I am waiting for him to tell me the name) he does not have the problem I do.

hope that Simulation Curriculum, Starry Night, would respond and help me. HELP!!



  • 0
    Ron Blackwell

    Hi John,

    I have Starry Night Pro 8.0.2, so maybe I can help.  If you look at the solar system from the ecliptic north (first 4 screens), you can see that Jupiter is moving as expected in its orbit.  If you position yourself opposite the dark side of the earth (screen 5) and center on Jupiter, then Jupiter appears to move toward the winter solstice as expected from February 1 to April 1, then away from the winter solstice until September 1 (see screens 6 to 8).  I can't tell for sure that this is what you're seeing because I don't know your observing location, but I think the software is operating correctly at least on my computer.



  • 0
    John Pendleton

    Hello Ron.

    Thanks for writing and for giveing screen views.

    This is what I do:

    1--- Location-- sun surface

    2--- 90°N on sun surface.

    3--- I go straight up from sun north pole about 5-15AU

    4--- I select the 4 inner planets with their drawn orbits, plus Jupiter with its drawn orbit

    5--- When I advance the days in that point (top left menu area), a day at a time, Jupiter

    goes around the sun in 25-26 days. A complete orbit!! Can't be.

    6--- What am I doing wrong or set up wrong?

    7--- Relative to the sun do the planets go clockwise OR counterclock wise?



  • 0
    Keiron Smith

    I figure out what the problem is.  When you select to go to the surface of the Sun, 90°N, you are on the surface, and as such turn as the Sun turns.  This does not change as you ascend straight up into space.  Your position in space is pivoting with the turning of the Sun.  What you are looking for is a Fixed Position in space.  To do this add another step, # 3.5, and choose Options > Viewing Location > View From: Stationary Location (do not change anything) > View From Selected Location.  Now continue with #4, etc, observe the orbit of the planets as you advance day by day.

    Starry Night is fine.  Problem is solved.

    Thanks, Ron, for your assist.

    Thanks, John, for your patience.

  • 0
    Ron Blackwell

    Hey John,

    If you turn on constellation labels, asterisms and boundaries at step 3, you can really see the sun's rotation against the background of stars.

  • 0
    John Pendleton

    Hello Keiron.

    You got it! That was it. Jupiter went around in 26 days

    because the sun turns in 26 days!

    I did what you said and now the system works EXACTLY like I

    need it to work.

    God bless you to know and do His will!

    John Pendleton

    PS--- When I did the additional steps you suggested,

    a window appears on the left. I did a print screen into Paint -jpeg-- see below

    what do I do with this or how to remove it????

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