NGC 2440 lies about 4000 light-years from the Sun, and given its size (about 74 arc-seconds by 42 arc-seconds), must be nearly 100 thousand AUs (approximately 1 1/2 light years) across, in its longest dimension, with a central star of 14th magnitude (visual). The planetary nebula must be relatively young, as its white dwarf is one of the hottest known (more than 200 thousand Kelvins, or about 400 thousand Fahrenheit), and despite its small size (about 1/40 the size of the Sun, or 2 to 3 Earth diameters), is perhaps 250 times brighter than our Sun. The complex structure of the nebula (shown in more detail in the second image), indicates several episodes of mass ejection, in different directions. Both images are "false-color" images, intended to bring out detail which would not be visible in the essentially monochrome view which the human eye would perceive, but the first is meant to at least approximate "natural" colors, while the second makes no effort to do so.