Halo Artifacts Around Bright Stars

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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).

• Altair in Aquila, V 0.76, Lowell 13-inch camera, Vol 1, p. 230
• Capella in Auriga, V 0.08, Lowell 13-inch telescope plate, Vol. 1, p. 262
• Arcturus in Bootes, V -0.05, Lowell 13-inch astrograph, Vol. 1, p. 305
• Sirius in Canis Major, V -1.46, Lowell 13-inch telescope, Vol. 1, p. 388
• Castor and Pollux in Gemini, V 1.9 and V 1.14, Lowell 13-inch camera, Vol. 2, p. 919
• Betelgeuse in Orion, V 0.42, Lowell 13-inch camera, Vol. 2, p. 1288
• Delta, Epsilon and Zeta Orionis, V 2.41, V 1.69, and V 1.90, Lowell Observatory, Vol. 2, p. 1304
• Mirfak in Perseus, V 1.79, Lowell 5-inch camera, Vol. 3, p. 1406
• Antares in Scorpius, V 0.91, Lowell 5-inch Cogshall camera, Vol. 3, p. 1662
• Aldebaran in Taurus, V 0.86, Lowell 13-inch camera, Vol. 3, p. 1811
• Pleiades in Taurus, Lowell 13-inch astrographic telescope, Vol. 3, p. 1870
• Polaris in Ursa Minor, V 2.02, Lowell 13-inch telescope, Vol. 3, p. 2013

Star images with halos published in Sky & Telescope articles from my home library include the following:

• Delta Geminorium with Pluto, V 3.53, Lowell 13-inch telescope (29 Jan 1930), S&T Feb 1976, p. 108
• Tau Canis Majoris, V 4.40, Boyden 60-inch reflector (1939), S&T Feb 1978, p. 189
• HD 112887 in Coma Berenices, V 7.17, 4-meter Kitt Peak telescope (1973), S&T Jan 1979, p. 13
• HD 226868 (Cygnus X-1), V 8.91, Hale Observatories, S&T Mar 1980, p. 235
• Zeta & Sigma Orionis, V 1.90 & V 3.79, 1.2-m Royal Observatory telescope, S&T Nov 1981, p. 416
• Regulus in Leo, V 1.40, 5.5-inch f/1.65 Schmidt camera, S&T Apr 1990, p. 459
• HD 164402 in Sagittarius, V 5.77, Anglo-Australian Observatory, S&T Dec 1996, pp. 20-21
• HD 198639 in Cygnus, V 5.07, 7-inch f/7 Astro-Physics refractor, S&T Dec 1996, p. 111
• Rigel in Orion, V 0.13, S&T Jul 1998, p. 127
• BD+46 3475 in Cygnus, V 9.69, 3.6-m Canada-France-Hawaii telescope, S&T Feb 2004, pp. 56-57
• Mizar & Alcor, V 2.22 & V 4.01, Digitized Sky Survey, S&T Jul 2004, p. 72
• HD 197912 in Cygnus, V 4.23, Kitt Peak WIYN 0.9-meter telescope, S&T Sep 2004, pp. 28-29
• HD 173582 and HD 173607 in Lyra, V 5.01 & V 5.21, Digitized Sky Survey, S&T May 2019, pp. 22-23
• HD 188947 in Cygnus, V 3.88, Digital Sky Survey, S&T Sep 2019, p. 57
• HD 41335 in Monoceros, V 5.21, S&T Jan 2023