WR 102ea
WR 102ea is a Wolf–Rayet star in the Sagittarius constellation. It is the third most luminous star in the Quintuplet cluster after WR 102hb. With a luminosity of 2,500,000 times solar, it is also one of the most luminous stars known. Despite the high luminosity it can only be observed at infra-red wavelengths due to the dimming effect of intervening dust on visual light. It is an evolved massive star which has an emission line spectrum from a strong stellar wind caused by high luminosity and the presence of elements heavier than hydrogen in the photosphere . The spectrum is dominated by ionised helium and nitrogen lines due to convectional and rotational mixing of fusion products to the surface of the star. However it is still in a core hydrogen burning phase and hydrogen lines are also visible in the spectrum, in contrast to WN stars without hydrogen which are older, less massive, and less luminous. Despite being a relatively unevolved star, WR 102ea has lost over half its mass already.