Behold Jupiter's Ghost — a spectacular remnant of a star that was once quite similar to our own. Located 3,000 light-years away, it's a sneak preview of what our solar system could look like once our Sun enters into its death throes.
Our Sun is not big enough to go supernova. Stars with masses from 0.8 to 8 times that of our sun gradually expand during their end-stage, releasing their outer layers in the surrounding space. The result, as beautifully demonstrated by this Hubble pic of Jupiter's Ghost, is a spectacular cloudy shell of dust, hydrogen, helium, and other ionized gases we call a nebula.
The ESA explains more:
The image reveals how mighty winds released by the dying star – the white dwarf star at the centre – are shaping the double-shell structure of the nebula. The blue glow filling the inner bubble represents X-ray emission from hot gas, heated up to over two million degrees by shocks in the fast stellar winds, gusting at about 2400 km/s against the ambient gas.
The green glow marks cooler concentrations of gas seen in optical light through the emission of oxygen, revealing the edge of the inner shell in contrast to the more diffuse gas making up the outer shell. The two flame-shaped features, visible in red to the upper right and lower left of the inner bubble, are pockets of even cooler gas, seen also in optical light through the emission of nitrogen.
As an aside, this planetary nebula — or NGC 3242 — has nothing to do with Jupiter or planets. The name harkens back to a time when astronomers mistook the round appearance of nebulas for planets. And it's called "Jupiter's Ghost" because the nebula spans a disc on the sky about the same size of Jupiter.
Image credit: ESA/XMM-Newton & Y.-H. Chu/R.A. Gruendl/M.A. Guerrero/N. Ruiz (X-ray); NASA/ESA Hubble Space Telescope & A. Hajian/B. Balick (optical).