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I am trying to calculate what would the Google maps latitude and longitude be, for a given location, 1000 east from it. I am not looking for an application which can do, this, but rather a manual way, by using equations.

I found out that there is a way of doing this, if one would know the initial bearing Angle:

bearingAngle = 90
d = 1000 kilometers / 6371 kilometers
x = asin( sin lat1 * cos d + cos lat1 * sin d * cos bearingAngle)
y = lon1 + atan2( sin bearingAngle * sin d * cos lat1, cos d - sin lat1 * sin x)

(Equations are taken from: movable-type.co.uk/scripts/latlong.html, section "Destination point given distance and bearing from start point")

However, the upper equations are giving the following result:

enter image description here

As you can see the "x,y" location has a bit lower latitude then starting "lan,lon" (Paris). Basically this is what I am trying to achieve:

enter image description here

The problem is that, to do this, I need to know the initial "bearing angle", which I do not.

How can I solve this problem?

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closed as off-topic by Vince, Brad Nesom, Mapperz♦ Oct 19 '15 at 20:28

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions describing a problem that can't be reproduced and seemingly went away on its own (or went away when a typo was fixed) are off-topic as they are unlikely to help future readers." – Vince, Brad Nesom, Mapperz
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  • A thousand kilometers is a long distance to travel using a spherical earth model. The geodetic inverse problem could solve the bearing and distance between two points short of antipodal distance, much as the direct geodetic problem can solve location for strating point, distance, and bearing. – Vince Oct 19 '15 at 18:17
  • Thank you for the reply Vince. The "Second (inverse) geodetic problem" you are mentioning requires the second point (its latitude and longitude) to be known. Which is not known in this case. – Bernard Oct 19 '15 at 18:28
  • If you don't know the point or the bearing, the problem can't be solved. – Vince Oct 19 '15 at 19:15
  • If you use units of radians in computer trig functions, they're more likely to produce correct results. – Vince Oct 19 '15 at 19:39
  • All upper variables are in radians (except for the "d" - angular distance). I checked the calculated "x","y" variables on Google maps. And they correspond the upper first photo. I thought this problem could have been solved somehow by replacing "x" to be equal to "lat", and from there (by using a formula for bearingAngle) somehow calculating the "bearingAngle", and after that "y". – Bernard Oct 19 '15 at 20:08