Halo artifacts are almost always seen in bright star images. These are Fraunhofer diffraction patterns associated with circular apertures. In the case of Origin, the additional diffraction tail like this one in Betelgeuse (upper left), is caused by the camera cable at the front end of the instrument. I call this the "tadpole pattern". For many significantly bright stars, however, these tails are not always visible.
There are many good examples of halo artifacts in the three volumes of Burnham's Celestial Handbook (Dover Publications, Inc., New York, 1978).
Star images with halos published in Sky & Telescope articles from my home library include the following:
Origin's diffraction pattern for Aldebaran in Taurus is shown here. There are several near-circular ridges that are caused by the circular aperture. I have highlighted them with dashed circles. The deviations from perfect circles, and the tail on the upper left, arise from the camera cable that connects the external sensor to the onboard computer. I added a black dashed circle at the centre of the bright Airy disk, named after mathematician and astronomer G. B. Airy, who first developed the normal irradiance equation for circular apertures in 1835 ( Radiation and Optics, John M. Stone, McGraw-Hill Book Company, New York, 1963, pp. 175-176).
Additional references
In this section I compare the Origin diffraction pattern for Mirfak (33 Persei) in Perseus to the pattern in the Second Generation Digital Sky Survey (DSS2). A link to Mirfak in the Simbad Database and DSS2 is made by selecting the action button "Link to Mirfak in Simbad".
Origin captured the 1.27° x 0.85° field centred on Mirfak on the evening of January 25, 2025. Because the outside temperature was -7°C at the time, a hot pixel appeared in the image as shown with the red label and arrow. Several reference stars, ordered by decreasing visual magnitude, have been labeled in white with Simbad links provided in the next section.
The Origin Airy disk is much smaller than the DSS Airy disk, the latter extending out to the yellow dashed circle labeled DSS Inner Disk. All of the stars revealed by Origin within the yellow circle, such as GAIA DR2 441700484037998720, are hidden behind the DSS Mirfak Airy disk, originally created with the 48-inch Oschin Schmidt Telescope at the Palomar Observatory. Many stars between the DSS inner disk (yellow) and DSS outer halo limit (blue) such as BD+49 913, can be seen in both Origin and DSS.
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