Navigate to <https://afterglow.skynet.unc.edu/en/workbench?tool=display>\
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Open both Alpha Centauri files in the Sample directory.

Select both Alpha Centauri images from the "Select Images to Align" dropdown.

Select either file from the "Reference Image File" dropdown.

Select both Alpha Centauri images from the "Select Images to Stack" dropdown.

Select the new file that was created (above the other two). In my case it was named simply ".fits"

Use the Display settings until you can see four blobs (two pairs of overlapping blobs)

Measure the distance between the two images of Alpha Centauri B. \
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NOT the distance between Alpha Centauri A and Alpha Centauri B.

Click once on the image to set the measurement's start point, move your mouse, then click a second time to set the end point.

0
0.5
1
1.5
2
2.5
110
115
120
125
1D Cross Section
Mode
Centroid clicks
Planet Centroiding
Interpolate pixels
Sync Plot Across Files
Measurement	Value
Start	
367.75, 498.528
+14:39:30.519, -60:50:6.747

End	
366.538, 495.911
+14:39:30.429, -60:50:8.308

Length	
2.885 pixels
1.695 arcsecs
0.0282 arcmins

Orientation	
204.842 degrees CW of +Y
202.905 degrees E of N

Copy your measurement in arcsec into your assignment. Then continue following the calculations in the assignment.

How to Measure Stellar Angular Shift