Omi-1

Its story

Omicron-1 Orionis is a remarkable rarity: a red giant of the unusual S class, an intermediate stage on the road from an ordinary M giant to a true carbon star, where zirconium begins to displace titanium in its atmosphere. A semi-regular variable, it drifts between magnitudes 4.65 and 4.88 every 31 days. At 651 light-years it pulses discreetly, far from the Belt's glitter, on Orion's northwestern shoulder.