Through the following form you can search a series of graphs where the proper motions are represented. In each graph, the gray line represents the average proper motions obtained from the position measurements. The blue line is the path smoothed by a polynomial adjustment. The points on this line represent the normalized positions at 12h UT of each day. If several spots appear on a graph, each setting uses a different color to identify them.

The graphs show the dates of the first and last data represented, in "aammdd" format. It must be borne in mind that all the days of the interval are included in the adjustment, but some of the data may be missing in the average trajectory. The average speed along the trajectory, angular velocity and rotation period between the first and last measurement is also added.

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Position measurements give us the heliographic coordinates of a spot, and with them you can build graphs that show your apparent movement over several days. This movement is apparent because it is the result, not only of one's proper motion, but also of differential rotation.

The network of heliographic coordinates rotates with the Sun with a period of 25.38d. This period corresponds to the solar rotation at 16º latitude. Due to the differential rotation, any detail of the surface located at more latitude, is being delayed, and therefore, has an apparent shift to the East. On the contrary, a detail located near the equator is ahead, so that its apparent displacement is towards the West. To correct this effect, the average latitude between two consecutive measurements is determined, and then the angle rotated is calculated by the following formula:

W = t * (14.37 - 2.6 * (sin lat) ^ 2)

where t is the interval (in days) between both measurements, and lat is the average latitude. This angle is the one that is subtracted from the displacement in length.

Once this effect is corrected, we obtain longitudes and latitudes, but they are no longer the heliographic coordinates defined by Carrington. In fact, they are relative coordinates whose reference is the first measure of the series. Therefore, in the graphs, the first measurement is always at the origin.

Another fact to keep in mind is that error in trajectories generally increases in the extremes, since the spot is closer to the limb introducing greater uncertainty in the positions. For that reason, the extremes of trajectories should always be interpreted with certain reservations.

Those spots with displacements lower than 1º have been considered static. Many times, these displacements are smaller than the size of the spot itself, and also, lower than the errors in the measurements, so they are unreliable. Those spots are included in the following list: