earth.twilights(forSunAltitude, coordinates) - Skips over SunSet Time for 10/17/2024

[johnnyturpin-aow]

Not able to find the sunSet time for 10/17/2024 - with a sunAltitude of .astronomical

To verify this, I created a loop where I called earth.twilights() repeatedly incrementing the JulianTime by 1 hour each iteration - and it never returns a sunSet time for 10/17/2024.

This only seems to occur with a sunAltitude of .astronomical. Weird.

Here are the results where it transitions from returning valid riset/set times for 10/16 - and then immediately jumps to 10/18

setRiseTransitTimes for: 10/17 at: 6:00 PM
sunRise = 10/17 at: 5:56 AM
sunSet = 10/16 at: 8:00 PM
transitTime = 10/17 at: 12:58 PM
transitError = None

setRiseTransitTimes for: 10/17 at: 7:00 PM
sunRise = 10/17 at: 5:56 AM
sunSet = 10/16 at: 8:00 PM
transitTime = 10/17 at: 12:58 PM
transitError = None

setRiseTransitTimes for: 10/17 at: 8:00 PM
sunRise = 10/18 at: 5:57 AM
sunSet = 10/18 at: 7:58 PM
transitTime = 10/18 at: 12:58 PM
transitError = None

setRiseTransitTimes for: 10/17 at: 9:00 PM
sunRise = 10/18 at: 5:57 AM
sunSet = 10/18 at: 7:58 PM
transitTime = 10/18 at: 12:58 PM
transitError = None

And here is the code snippit I am using to test this - nothing too complicated:

Note: computedTargetDay is set to 12:00 PM UTC-4 (Noon EST) on 10/17/2024

stepTime = computedTargetDay.addingTimeInterval(TimeConstants.secsInDay * -2)
endTime = stepTime.addingTimeInterval(TimeConstants.secsInDay * 4)
			
print("===== \(computedTargetDay.astroTime)")
while stepTime < endTime {
    let earth = Earth(julianDay: JulianDay(stepTime))
    let twilights = earth.twilights(forSunAltitude: twilightAltitude.rawValue, coordinates: geographic)

    print("setRiseTransitTimes for: \(stepTime.astroTime)")
    print("sunRise = \(twilights.riseTime?.date.astroTime ?? "")")
    print("sunSet = \(twilights.setTime?.date.astroTime ?? "")")
    print("transitTime = \(twilights.transitTime?.date.astroTime ?? "")")
    print("transitError = \(twilights.transitError?.localizedDescription ?? "None")")

    sunTimes.append(twilights)
    stepTime = stepTime.addingTimeInterval(TimeConstants.secsInHour * 1)
}