I know that Celestia does not take into account the light time delay. Therefore, what we see in Celestia is not what we should see in reality. And some astronomical phenomena cannot be seen with Celestia (the phemus for instance).
Is this someting difficult to implement ?
It would really be nice to have an even more real Celestia
What do you think ?
---Paul
Light delay
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HankR
If I'm not mistaken, I seem to recall reading somewhere that NASA's SPICE library approximates light delay by calculating positions twice. First, it calculates an object's actual position at the current time and uses its distance from the observer to estimate the object's apparent time as seen from the observer's position. Then it recalculates the object's position at the estimated apparent time. This obviously is not exact, but evidently it's close enough for many purposes. This approach wouldn't seem to be too hard to implement, but it would slow things down a bit.
- Hank
- Hank
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chris
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HankR wrote:If I'm not mistaken, I seem to recall reading somewhere that NASA's SPICE library approximates light delay by calculating positions twice. First, it calculates an object's actual position at the current time and uses its distance from the observer to estimate the object's apparent time as seen from the observer's position. Then it recalculates the object's position at the estimated apparent time. This obviously is not exact, but evidently it's close enough for many purposes. This approach wouldn't seem to be too hard to implement, but it would slow things down a bit.
If you want more accuracy, you can just keep iterating . . . I'll add a light-time calculation to Celestia eventually, but it will definitely be an optional feature. If you're using Bruckner's 7000 asteroid .ssc file, you probably don't want to double (or triple, ...) the number of orbital computations.
--Chris
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Topic authorCalculus