The Time button in the main Sky Chart toolbar displays a set controls which let you flow the date and time dynamically, or adjust it step-by-step. Tap the Time button to show these controls; tap it again to hide them.
When visible, the time flow controls contain the following items:
Time Flow Arrows: Above the time units, a set of VCR controls lets you start and stop the flow of time. Tap the rightmost arrow to start the flow of time continuously forward; tap the leftmost arrow to flow time continuously backward. Tap either of these arrows to stop the flow of time.
Time Step Arrows: The central arrows adjust the time by a single step, equal to the time unit you have selected underneath. For example, if you selected 1 day as the time unit, tapping the center right arrow will move the time forward by 1 day - but it will not continuously run the time by one day.
Now Button: Stops the flow of time, and returns to the current date and time indicated by your Android device's internal clock.
Time Units: a row of buttons directly above the main toolbar lets you select the time unit you wish to change. Tap "Sec" to change the seconds, "Day" to change the day, "Year" to change the year, and so on.
In SkySafari Plus and Pro, the number to the left of the time unit buttons is a multipler applied to the time unit. You can tap this number to enter a new time step with a numeric keypad - for example: 10 minutes, 7 days, 80164 seconds (one sidereal day), or 24.659784 hours (one Martian day). Please Note: in the basic version of SkySafari, you can only use time steps of exactly one minute, one day, etc.
You'll find that different astronomical phenomena are best simulated using different time units. For example:
Second - best for showing the motion of fast-moving satellites.
Minute - best at showing the daily rise-and-set motion of the Sun, Moon, and Stars.
Hour - best for showing the motion of Jupiter and Saturn's moons.
Day - best for showing the motion of the planets against the background stars, as they (and we!) orbit the Sun.
Year - best for showing the orbital motion of binary star systems like Sirius and Alpha Centauri.
Time flow is temporarily paused when another view (like Search, Object Info, or Settings) is present. You can also use the Settings to change the simulated date and time. If you are using SkySafari to control a telescope, we do not reccomend using Time Flow while the telescope is connected - simulating a view other than the current date and time may result in pointing the telescope at the wrong place in the sky!