This episode's coordinates point to an object in the constellation Lupus, which represents a wolf. I would assume that you, like me, would not have guessed that the sky contained a constellation of a wolf, but it apparently does. This constellation dates back to ancient times, but interestingly, the Greeks referred to it as Therion, which was some sort of generic wild animal, and the Romans referred to it as Bestia, which was a very generic beast [1]. It seems to have only been definitively identified as a wolf sometime around the early 1600s [1].
The specific object that this episode's coordinates point to is a planetary nebula called Hen 2-113 sitting within the open cluster NGC 5822 at a distance of about 6900 light years (2.1 kpc) from Earth [2, 3]. This might sound like the designation for some sort of genetically engineered chicken. However, the Hen in the name for this object refers to Karl G. Henize, a mid-twentieth century astronomer who liked to observe stars in ultraviolet light and make catalogs of planetary nebulae, and Hen 2-113 ended up in one of those catalogs. As a side note, Henize was also an astronaut who flew on the space shuttle Challenger in 1985 [4]. Also, he passed away from high altitude pulmonary edema while climbing Mount Everest in 1993 [4].
Anyway, back to Hen 2-113. The most important thing to keep in mind about this object is that it is not a typical planetary nebula. Normal planetary nebulae form when stars about the size of the Sun die. The core of such a star will fill up with helium, the star will then transform into a red giant, some other stuff happens, and then eventually the fusion of helium into carbon and oxygen will be triggered in the center of the star. However, the star will not be massive enough to exert the pressures in its core needed to create heavier elements, so once the star's core fills up with carbon and oxygen, it will blow away its outer atmosphere to form a planetary nebula with the core becoming a faint white dwarf at the center of the nebula.
Hen 2-113, however, does not have a faint white dwarf at its center but instead a rather large and rather bright Wolf-Rayet star. I suppose finding a Wolf-Rayet star within a constellation representing a wolf makes sense in some ways. Anyway, I've already mentioned Wolf-Rayet stars a couple of times in this podcast series. This class of stars was discovered in 1867 by Charles Wolf and George Rayet [5], and they were initially characterized by their weird spectra, which showed evidence of huge winds coming from the surfaces of these stars.
Wolf-Rayet stars are 10 to 25 times more massive than the Sun. Hence, these stars are large enough that, when they have reached the stage in their evolution where their cores fill up with carbon and oxygen, the central pressures are high enough to trigger the fusion of those elements into even heavier elements. Wolf-Rayet stars produce such extreme amounts of energy that they blow away their outer hydrogen layers, which means that it's possible to see layers within these stars where fusion is taking place. The hydrogen that gets blown away goes on to form planetary nebulae that are referred to specifically as Wolf-Rayet planetary nebulae. One of the notable things about these types of objects generally as well as about Hen 2-113 specifically is that they expel lots of elements heavier than hydrogen and helium into the interstellar medium, some of which is in the form of dust grains that go on to become interstellar dust, and this is important in terms of understanding how these elements get into the interstellar medium in the first place, especially since the material goes into the formation of new stars and new planets.
Additionally, Hen 2-113 is an especially interesting Wolf-Rayet planetary nebula because it has a rather complex structure, with the nebula appearing to extend outwards from the star in four different directions, and these gas layers seem to be moving in very complex ways [6, 7, 8]. Modelling these structure has been especially challenging for many astronomers. Nonetheless, they have spent quite a bit of time studying Hen 2-113 because its complex structure can provide more general insights into how gas flows outwards from Wolf-Rayet stars to form planetary nebulae.