NGC 2371, located in the constellation Gemini approximately 4300 light-years distant, is a double lobed planetary nebula surrounding a dying Sun-like star.  The outer layers of the star have been violently ejected forming the nebula.  The remaining core of the star can be seen in the center of the nebula.  Although the nuclear fuel powering the star has been depleted, the core has gravitationally collapsed and is extremely hot with an estimated temperature of 240,000 degrees Fahrenheit.  The intense ultraviolet radiation from the remnant star ionizes the surrounding gases and causes them to glow much like that of a neon light.  The surrounding nebula is expanding and will, in a few thousands of years, dissipate into space.  With no fuel available, the core temperature will gradually cool and, in the far distant future, become just a burned out cinder floating in space.

The image above was assembled from narrowband, Ha and OIII, filtered data.  Ha was mapped to Red and OIII was mapped to Blue.  A 'detection, or white-light, image' consisting of a combination of the Ha and OIII frames was mapped to Green.

¹http://hubblesite.org/newscenter/archive/releases/2008/13/image/a/