Ya know, given the (expected) sensitivity around here to "dragon-king" events; very-low probability occurrences at the extreme tail of the PDF, as well as energy considerations, there might be some interest in a low-probability explanation for this:
<a href="http://www.sci-news.com/astronomy/science-nasty-1-wolf-rayet-star-02829.html" rel="nofollow">Nasty 1: Hubble Uncovers Surprising New Clues about Unique Wolf-Rayet Star</a><blockquote>Nasty 1 is also known as Wolf-Rayet 122 or WR 122. The star’s catalogue name, NaSt1, is derived from the first two letters of each of the two astronomers who discovered it in 1963, Jason Nassau and Charles Stephenson.</blockquote><blockquote>The star lies at a distance of about 3,000 light-years and is thought to be a Wolf-Rayet star – a massive, rapidly evolving star weighing well over 10 times the mass of our Sun. It is losing its hydrogen-filled outer layers quickly, exposing its super-hot and extremely bright helium-burning core.</blockquote><blockquote>But Nasty 1 doesn’t look like a typical Wolf-Rayet star. [...]</blockquote><blockquote>Instead, they revealed a pancake-shaped disk of gas encircling the star. The vast disk is nearly 2 trillion miles wide, and <b>may have formed</b> from an unseen companion star that snacked on the outer envelope of the newly formed Wolf-Rayet. [my bold]</blockquote>IOW, they don't really know how or why this object formed. Actual article: <a href="http://mnras.oxfordjournals.org/content/450/3/2551.full.pdf+html" rel="nofollow">Multiwavelength observations of NaSt1 (WR 122): equatorial mass loss and X-rays from an interacting Wolf–Rayet binary</a>.<blockquote>NaSt1, aka WR 122, is an evolved massive star that has defied characterization. It was discovered by Nassau & Stephenson (1963), who proposed a WR classification based on the strong emission-line spectrum. It was later reclassified [...] then later proposed to be [...] Subsequently, more detailed multiwavelength investigation by Crowther & Smith (1999, hereafter CS99) showed that although NaSt1 is indeed a hot luminous object with [...], its emission-line spectrum is mostly of nebular origin, not stellar. Moreover, ground-based narrow-band imaging through an [N ii] filter centred near wavelength λ6584 Å revealed the presence of a compact circumstellar nebula with a diameter of ≈7 arcsec, [...]</blockquote><blockquote>[...] CS99 pointed out that the only other massive star known to be enshrouded in a nebula having a comparable level of nitrogen enrichment is the LBV+OB binary η Car and its Homunculus nebula ([ref's]). However, CS99 note that the chemical abundance ratios in the NaSt1 nebula are characteristic of a WR, and probably inconsistent with a red supergiant or H-rich LBV. Moreover, the derived ionization potential requires that the central ionizing source be T ≫ 30 kK, which suggests a spectral subtype earlier than WN6–7. The absence of the characteristic broad emission lines from a WR wind, however, implies that the stellar system is deeply embedded in an opaque nebula. High-resolution spectroscopy by CS99 revealed that the nebular lines have a double-peaked morphology, which suggests <b>complex geometry for the outflow.</b> [my bold]</blockquote>
In summary, the object is totally unique, with a few similarities to other known objects, but also clear differences. All the "explanations" offered for it are completely speculative, suitable only because nothing better is on the table. Here's my thought:
This object could well be a major power station, created by a life-form with human style intelligence and engineering ability. It's encircled by a disk roughly 10 times the size of the Earth's orbit, which is radiating a huge amount of energy into space. Although that disk is hot enough to be fully ionized, allowing all sorts of chaotic <b>or engineered</b> <a href="http://en.wikipedia.org/wiki/Magnetohydrodynamic_turbulence" rel="nofollow">magnetohydrodynamic (MHD)</a> turbulent structures, its temperature is very low compared to that of the stellar core, potentially allowing energy to be shipped from the core to the radiating disk with almost all of it extracted in useful form. (If the absolute temperature of the source is 10 times that of the radiating disk, the Carnot efficiency would be ~90%.)
It's certainly plausible that our current technology, at the rate it's going, might be able to create such a stellar-sized power station (using, for instance, the double star <a href="http://en.wikipedia.org/wiki/Alpha_Centauri" rel="nofollow">Alpha Centauri</a>) through MHD engineering, within a century or two. I'm not sure what "we" would use all that energy <b>for</b>, but I'm sure something would come up. Perhaps an interstellar civilization with a population in the 1,000,000,000,000,000's.
Given that, I don't see how we can rule out deliberate engineering by a life-form with human-style intelligence as an explanation for something like NaSt1/WR 122.