This is the aftermath of an exploding star (G299, by name) and it's undoubtedly beautiful. But what it also is is very, very strange — and it just might turn all that we know about how stars explode on its head.
Understanding just how a white dwarf goes supernova is a relatively new revelation, but one part that scientists did believe they had a handle on was the fact that, when white dwarfs explode, they tend to explode symmetrically in all directions.
But, as you can see clearly above, the progress of this particular supernova has been rather splendidly uneven.
There are two possible explanations for this, explains NASA. One is that the explosion was, as expected, symmetrical, but variations in space are responsible for the supernova's strange expansion. Perhaps, but the more compelling explanation, say the researchers, is that the explosion itself was uneven:
By performing a detailed analysis of the X-rays, researchers found several clear examples of asymmetry in G299. For example, the ratio between the amounts of iron and silicon in the part of the remnant just above the center is larger than in the part of the remnant just below the center. This difference can be seen in the greener color of the upper region compared to the bluer color of the lower region. Also, there is a strongly elongated portion of the remnant extending to the right. In this region, the relative amount of iron to silicon is similar to that found in the southern region of the remnant. The patterns seen in the Chandra data suggest that a very lopsided explosion may have produced this Type Ia supernova.