3

I'm using an API which returns a satellite's PVCoordinates (Position/Velocity pairs).

{P(1036869.5330731269, 6546536.584960848, 9.892293545390519E-11), V(-9994.355195123433, 1582.9503539842497, -1242.4491245907245)}

Given an array of these PV coordinates, how can I calculate or derive latitude and longitude coordinates for the nadir line (ground sub-track)?

Does anyone know of a Java API which might help me or is the math easy enough that I can write a function myself? (Full Disclosure: I have a math disorder)

Nadir line example

I've looked around the web and everything I see tends to make my eyes glaze over and humble me to the point of wishing my pathetic self should have taken more math in college.

  • 2
    Doesn't the thread at gis.stackexchange.com/questions/34532/… answer this? Although it is in principle possible to use the velocity data to improve the plot of a track when the data are sparse, I can assure you the math will get harder :-). You need only a small part of my answer there: the (one-line) CartesianToEllipsoid function. – whuber Jan 10 '14 at 22:57
  • 1
    Have a look at the Orekit Corridor Track example. Around line 275 the sub-satellite track is computed. – rickhg12hs Jan 11 '14 at 10:07
  • @rickhg12hs Please copy/past your comment as an answer so I can give you credit. Thanks! – CaptDragon Jan 13 '14 at 15:30
  • Glad to help! Good luck! – rickhg12hs Jan 13 '14 at 18:59
1

The Orekit Corridor Track example shows how to calculate the sub-satellite track around line 275.

  • 1
    Works perfectly. – CaptDragon Jan 13 '14 at 19:20

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.