@@ -40,7 +40,7 @@ The mouse is used to draw circles, ellipses, rectangles, rotated rectangles, pol
- Meters (m) - Displays the distance between the endpoints of the line in meters. This requires a spiceinit'ed or projected cube. The distance is calculated by converting the endpoints to their corresponding latitudes and longitudes and then using a great circle algorithm to calculate the distance between them.
- Kilometers (km) - Displays the distance between the endpoints of the line in kilometers. This requires a spiceinit'ed or projected cube. The distance is calculated in the same manner as for "meters" and converted to kilometers.
- Pixels - Display the distance between the endpoints of the line in pixels. This option is always available for any cube. The distance is calculated using the Pythagorean theorem.
- Planer Kilometers - Displays the distance between the endpoints of the line in kilometers. This option is only available if there is a camera model available for the image and at least one of the points is on the surface of the target body defined in the cube label. The distance is calculated using the angle between the right ascension and declination of the two endpoints, and the slant range distance from the spacecraft to the point on the target surface. An isosceles triangle is assumed between the first point, the spacecraft, and the second point. The reported distance is the length of the base of the triangle. The equation used for this calculation is below. dec1, dec2, RA1, and RA2 refer to the right ascension and declination of the starting and ending point of the line, respectively.
- Planer Kilometers - Displays the distance between the endpoints of the line in kilometers. This option is only available if there is a camera model available for the image and at least one of the points is on the surface of the target body defined in the cube label. The distance is calculated using the angle between the right ascension and declination of the two endpoints, and the slant range distance from the spacecraft to the point on the target surface. An isosceles triangle is assumed between the first point, the spacecraft, and the second point. The reported distance is the length of the base of the triangle. The equation used for this calculation is below. dec1, dec2, RA1, and RA2 refer to the right ascension and declination of the starting and ending point of the line, respectively, and d_slant is the slant range of the point on the target body, which can be obtained from the camera model.
