STAR Atlas:PRO frequently asked questions - FAQs
Can I animate Jupiter's Moons back and forward through time ?
Yes. The Jovian Event facility permits you to do exactly that! You can search forward (and back) through time for events you wish to observe, such as a Moon transiting the face of Jupiter, or one moon eclipsing another.
Here is how:-
1. Open Star Atlas: PRO.
2. Click on [Locate] on the main menu.
3. Under [Other Objects] (bottom right) click [41 � Jovian Events]
4. This brings up the Jovian Events information panel and menu, which shows where the moons are positioned in relation to Jupiter (for the current instant in time).
5. Set the Number of Frames option to 20 (bottom centre)
6. Set the Delay between Frames option to 10 (bottom centre)
7. Click the [Hours - 1] button (bottom right) which will set the Time Skipped
between Frames value to 60 minutes.
8. Now click the [Time Skip - Forward button] (at lower left) and the Moons of Jupiter will now begin orbiting Jupiter in real-time, automatically.
9. While the Animation is in progress press the ESC key on your keyboard
10. The Date and Time for the current Moon positions are displayed for the instant where the animation was stopped by the ESC key (if you see an event that you wish to observe, immediately press ESC key and note the Date and Time).
Explanation of Animation Menu Options
Number of Frames: The [Number of Frames] is a preset which allows the user to advance forward (or backward) through time to a preset time i.e. If the [Number of Frames] is preset to  and the [Time Skipped between Frames] is [12 hours = 720 minutes] then the [Time Skip � Forward] button will advance the program time by 2*12 = 24 hours = 1 day (you can check this by observing the time on the[Date & Time] section.
Delay between Frames: The interval between each frame update (in 1/10ths of a second). This button set the time between �Skips�. Too short means that the program goes too fast and does not allow the viewer time to judge what is happening, too long and the computer will take and age to move forward.
Time Skipped between Frames: sets the amount of Time (in minutes) that is skipped between each Frame (see Number of Frames above).
[Time Skip - Forward button]: The [Time Skip] button moves time forward (or backward) automatically so that the observer can just sit and watch.
[Time Step - Forward]: For finer control, the [Time Step] button is available which moves the time froward (or backward) manually and gives the viewer greater control.
11. Now click the [Time Step - Forward] button (lower left of screen) and the animation advances only one frame forward.
12. Now click the [Time Step - Reverse] button (lower left) and the animation reverses one frame backward.
13. Notice that each time you click the [Time Step - Forward or Reverse] buttons the displayed Date and Time also changes.
14. To continue the animation to the end, click the [Time Skip - Forward] button.
Have good viewing with this feature � you can enhance you interest of Astronomy with such aspects of STAR Atlas: PRO!
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