400 L ☉
Alphard ( from the Arabic al - fard الفرد " the single person " ) is the name of the star α Hydrae ( Alpha Hydrae ), the brightest star of the constellation Hydra. The star is also known as "Cor Hydrae " meaning " Dragon Heart ". Alphard has an apparent magnitude of 1.98 mag and is located at a distance of 180 light years. Alphard is an orange-red giant star of spectral type K3 with an absolute magnitude of -1.8 mag. Alphard has approximately 400 times the luminosity of our Sun. Its surface temperature is 4000 Kelvin. He is one with a diameter exceeding the the sun by 40.8 -fold, to the orange red giant stars. It thus belongs to the bright giants. Alphard has an optical companion (optical double star ) at a distance of 281 ' at 153 °, a blue star 10 size class without physical reference.