First fringes of the Sun, taken with the above interferometer
Samples are collected at 10 second intervals. There are 3 large peaks (a,b,c), these can be used to calculate the angular distance between the peaks comparing what it should look like mathematically to what has been recorded while the sun drifts through the beam of the antenna. Using the following formulae from Bill Lonc, Radio Astronomy Projects, 1996, we can substitute dimensions of the interferomter:
Sun drift scan angle in minutes = (angle * 4). Where 4 minutes = sideral time. The angle: angle = (lambda / Distance * Cos (Declination)) * (Pi/180)
where:
 lambda = 21cm
 Distance = 420cm (20*lambda)
 Declination = +1.71 degrees (sun angle, the dishes are at 27 degrees elevation)
 Pi radians = (Pi/180) = 57.29 degrees
So according to formula the minute spacing between the peaks in the interferogram should = 11.47 minutes. (Minutes = (Angle * 4 = (21cm / 420cm * .9992 ) * 57.3)).
How does the recorded data look by comparison? The number of minutes between the peaks in these data: from peak a to peak b = 11 minutes, from peak b to peak c = 13 minutes, the average = 12 minutes. How close is this to the theoretical? 11.47 minutes / 12 minutes = 95%
