This bright palette of violet and yellow colors represents the gas bubble NGC 3199, released by a WR18 star.
The Wolf-Rayet stars are massive, powerful and energetic stars that have reached the end of their existence. They fill their surroundings with thick, intense, fast-moving winds that push material out. This contributes to the creation of strange and amazing cosmic forms. These winds are capable of generating powerful shock waves when they collide with a cool interstellar medium. The process can heat the material to high temperatures, because of which X-rays are released.
This is exactly what happened with NGC 3199. This scenario has already been noted earlier, but it is still considered rare because only three such bubbles were found: NGC 2359, NGC 6888 and S308. WR18 is considered a star with especially powerful winds. As soon as the material for feeding the streams is over, it will explode as a supernova. The image was created with an EPIC camera at the XMM-Newton X-ray Space Observatory. Here different gas sections are marked with different colors. The incredibly hot diffuse X-ray gas inside the bubble is marked blue, and the bright arc in optical light is yellow-green (oxygen) and red (sulfur emission).
The blue and yellow-green components form an optical nebula — a bright cloud of dust and ionized gases stretching to the western end of the x-ray bubble. From behind the arc, it was previously believed that the WR18 was a runaway star moving much faster than expected. But later x-ray observations have disproved this idea.