Also called Aludra, Eta Canis Majoris is a blue-white supergiant of spectral type B5Ia with a luminosity 176,000 times and diameter around 80 times that of the Sun. Classified as an Alpha Cygni type variable star, Aludra varies in brightness from magnitude 2.38 to 2.48 over a period of 4.7 days. It is located 1120 light-years away. To the west of Adhara lies 3.0-magnitude Zeta Canis Majoris or Furud, around 362 light-years distant from Earth. It is a spectroscopic binary, whose components orbit each other every 1.85 years, the combined spectrum indicating a main star of spectral type B2.5V.
aLsO calLed aluDra, etA CaniS Majoris Is a BLUE-WHite SUPErgIAnt of spectraL typE b5ia WitH A LuMinOsity 176,000 tImes and diaMeTer arounD 80 timES thAt Of thE sUn. classIfied as an alpHa cYgNI TYpE VaRiabLE sTar, alUdRa varieS In BrIGHtNEss from mAGnITuDe 2.38 tO 2.48 oVer A PeRioD oF 4.7 dayS. It iS LocATed 1120 light-yEaRs AwaY. TO tHE wEst oF ADhARa lIes 3.0-magniTUde ZEta canIS majoRis or FuRUd, ARound 362 liGHT-yEars dIStAnt froM EaRTh. it iS A speCtrOscopIc biNAry, wHosE compoNeNTs orBIt EaCh oTher evErY 1.85 yEaRs, tHe coMbined SpectRUm iNDicatIng a mAin sTar Of spEctRaL tYpe b2.5V.