LMC195-1 is a

Wolf–Rayet star Wolf–Rayet stars, often abbreviated as WR stars, are a rare heterogeneous set of stars with unusual spectroscopy, spectra showing prominent broad emission lines of ionised helium and highly ionised nitrogen or carbon. The spectra indicate very ...

located in the

Large Magellanic Cloud The Large Magellanic Cloud (LMC) is a dwarf galaxy and satellite galaxy of the Milky Way. At a distance of around , the LMC is the second- or third-closest galaxy to the Milky Way, after the Sagittarius Dwarf Spheroidal Galaxy, Sagittarius Dwarf ...

(LMC). It is an extremely rare member of the WO oxygen sequence, at WO2 the hottest known in the LMC. It is likely to be one of the hottest stars known. The star was first observed in a 2013 survey of the Magellanic Clouds using the 1m Swope telescope at

Las Campanas Observatory Las Campanas Observatory (LCO) is an astronomy, astronomical observatory managed by the Carnegie Institution for Science (CIS). Located in Chile's Atacama Region, it sits about northeast of the city of La Serena, Chile, La Serena. The LCO's telesc ...

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

. The survey was intended to identify Wolf–Rayet candidate stars by taking images through narrow-bandwidth filters centred on the 465.0 nm C_III and 468.6 nm He_II spectral lines together with a continuum filter at 475.0 nm. Digital subtraction of the separate images was used to highlight stars with particularly strong emission at one or both of the indicative spectral lines. The first survey of the Large Magellanic Cloud in October 2013 identified eight previously unknown candidate objects, of which five were later confirmed to be Wolf Rayet stars. LMC 195-1 is located in the rich LH-41 ( NGC 1910)

stellar association A stellar association is a very loose star cluster, looser than both open clusters and globular clusters. Stellar associations will normally contain from 10 to 100 or more visible stars. An association is primarily identified by commonalities in i ...

that contains the

luminous blue variable Luminous blue variables (LBVs) are rare, massive, evolved stars that show unpredictable and sometimes dramatic variations in their spectra and brightness. They are also known as S Doradus variables after S Doradus, one of the brightest stars of th ...

S Doradus S Doradus (also known as S Dor) is one of the brightest stars in the Large Magellanic Cloud (LMC), a satellite galaxy of the Milky Way, located roughly 160,000 light-years away. The star is a luminous blue variable, and one of the List ...

as well as another WO star LH 41-1042. The two WO stars are only 9" apart. WO stars are classified on the basis of O_VI emission at 381.1-383.4 nm, which is weak or absent in other Wolf–Rayet stars. The WO2 subclass is defined as having the ratio of O_VI to O_V emission strength between four and 12.5. Higher values would indicate WO1, while smaller values would be WO3 or WO4. In the new star, the ratio of these line strengths was 4.5.

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See also