Variations in the profiles of Alpha Camelopardalis' spectral lines are caused by fluctuations in the photosphere and stellar wind. This may be caused by non-radial pulsations. The absorption lines in the optical spectrum show radial velocity variations, although there is significant uncertainty about the period. Estimates range from a period as low as 0.36 days up to 2.93 days. The stellar wind from this star is not smooth and continuous, but instead shows a behavior indicating clumping at both large and small scales.[10] This star is losing mass rapidly through its stellar wind at a rate of approximately 6.3 × 10−6solar masses per year,[5] or the equivalent of the mass of the Sun every 160,000 years.
In 1968, this star was classified as a spectroscopic binary, indicating that it has an orbiting stellar companion with a period of 3.68 days and an orbital eccentricity of 0.45. Subsequent studies refined the period to 3.24 days. However, in 2006 it was recognized that the changes in the spectrum were probably the result of changes in the atmosphere or stellar wind, so it is more likely a single star.[11] Speckle interferometry observations with the 3.67 m Advanced Electro Optical System Telescope at the Haleakala Observatory failed to detect a secondary component.[12]
In 1961, based on the criteria that the proper motion of this star indicates a space velocity of greater than 30 km/s,[13] Alpha Camelopardalis was suggested as a candidate runaway star that had been ejected from the cluster NGC 1502. This was based upon the kinematic properties of the star and cluster, as well as the location of this star at a high galactic latitude in an area otherwise lacking in stellar associations. Over the course of a million years, this star should have moved only 1.4° across the sky, while it was estimated as being only two million years old.[7]
Runaway stars such as this with a stellar wind that is moving at supersonic velocity through the interstellar medium have their wind confined by a bow shock due to ram pressure. The dust in this bow shock can be detected using an infrared telescope.[14] Just such a bow shock was observed with NASA's Wide-field Infrared Survey Explorer, or WISE. The star is traveling at a rate of somewhere between 680 and 4,200 kilometers per second: between 1.5 and 9.4 million mph.[15]
^ abcdDucati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
^Sota, A.; Maíz Apellániz, J.; Walborn, N. R.; Alfaro, E. J.; Barbá, R. H.; Morrell, N. I.; Gamen, R. C.; Arias, J. I. (2011). "The Galactic O-Star Spectroscopic Survey. I. Classification System and Bright Northern Stars in the Blue-violet at R ~ 2500". The Astrophysical Journal Supplement. 193 (2): 24. arXiv:1101.4002. Bibcode:2011ApJS..193...24S. doi:10.1088/0067-0049/193/2/24. S2CID119248206.
^ abMarkova, N. (April 2002), "Spectral variability of luminous early type stars . II. Supergiant alpha Camelopardalis", Astronomy and Astrophysics, 385 (2): 479–487, Bibcode:2002A&A...385..479M, doi:10.1051/0004-6361:20020153 See Table 1.
^ abBlaauw, A. (May 1961), "On the origin of the O- and B-type stars with high velocities (the "run-away" stars), and some related problems", Bulletin of the Astronomical Institutes of the Netherlands, 15: 265, Bibcode:1961BAN....15..265B
^Aveni, A. F.; Hunter, H. J. Jr. (October 1967), "Observational studies relating to star formation. I.", Astronomical Journal, 72: 1019–1027, Bibcode:1967AJ.....72.1019A, doi:10.1086/110378
^Gies, D. R. (July 1987), "The kinematical and binary properties of association and field O stars", Astrophysical Journal Supplement Series, 64: 545–563, Bibcode:1987ApJS...64..545G, doi:10.1086/191208
^Noriega-Crespo, Alberto; van Buren, Dave; Dgani, Ruth (February 1997), "Bow Shocks Around Runaway Stars.III.The High Resolution Maps", Astronomical Journal, 113: 780–786, Bibcode:1997AJ....113..780N, doi:10.1086/118298
