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EspañolALPHARD
:''Alphard is also the name of a programming language.
'Alphard' (α Hya / α Hydrae / Alpha Hydrae) is the brightest star in the constellation Hydra, marking the heart of the snake.
Alphard is an orange giant star. The name Alphard is from the Arabic 'فرد|الفرد ' (''Al Fard''), "the solitary one."
Precise radial velocity measurements [1] have shown variations in the stellar radial velocities and spectral line profiles. The oscillations are multi-periodic with periods from several hours up to several days. The short-term oscillations were assumed to be a result of stellar pulsations, similar to the solar ones. A correlation between the variations in the asymmetry of the spectral line profile and the radial velocity has also been found. The multi-periodic oscillations make HD 81797 (Alphard) an object of interest for asteroseismologic investigations.
1. Setiawan, J., Roth, M., Weise, P., Dölinger, M. P. (2006) Multi-periodic oscillations of HD 32887 and HD 81797. ''Memorie della Societa Astronomica Italiana'', '77', p.510
'Alphard' (α Hya / α Hydrae / Alpha Hydrae) is the brightest star in the constellation Hydra, marking the heart of the snake.
Alphard is an orange giant star. The name Alphard is from the Arabic 'فرد|الفرد ' (''Al Fard''), "the solitary one."
Precise radial velocity measurements [1] have shown variations in the stellar radial velocities and spectral line profiles. The oscillations are multi-periodic with periods from several hours up to several days. The short-term oscillations were assumed to be a result of stellar pulsations, similar to the solar ones. A correlation between the variations in the asymmetry of the spectral line profile and the radial velocity has also been found. The multi-periodic oscillations make HD 81797 (Alphard) an object of interest for asteroseismologic investigations.
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| References |
References
1. Setiawan, J., Roth, M., Weise, P., Dölinger, M. P. (2006) Multi-periodic oscillations of HD 32887 and HD 81797. ''Memorie della Societa Astronomica Italiana'', '77', p.510
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