Image Credit: ESO
IC 1295 is a planetary nebula that lies some 3,300 light-years away from Earth in the constellation of Scutum (the Shield). It is moving toward us at about 13 kilometers per second.
The name of planetary nebulae arose in the 18th century because of the visual similarity between some round planetary nebulae and the planets Uranus and Neptune when viewed through small optical telescopes. The name has stuck even though modern telescopes make it obvious that these objects are not planets at all, but the glowing gassy outer layers thrown off by a hot dying star.
When a star with a mass up to eight times that of the Sun runs out of fuel at the end of its life, it blows off its outer shells and begins to lose mass. This allows the hot, inner core of the star (collapsing from a red giant to a white dwarf) to radiate strongly, causing this outward-moving cocoon of gas to glow brightly.
Planetary nebulae last for only about 10,000 years, a fleeting episode in the 10-billion-year lifespan of Sun-like stars. So, over the next several thousand years, IC 1295 will gradually disperse into space, and then the white dwarf will cool and fade away for billions of years. Over about 5 billion years from now, our own Sun is expected to undergo a similar fate.
IC 1295 consists of multiple shells, gaseous layers which once were the star’s atmosphere. This ghostly green bubble is surrounding the dim and dying star which is illuminating the nebula and making it glow. The color depends on the make up of gas. Green comes from ionized oxygen particles. The star, now a white dwarf, can be seen in the center of the nebula as a blue/white spot. Although doomed the white dwarf will still take many billions of years to cool down.
This image is taken with the FORS1 instrument on ESO’s Very Large Telescope, by using three different color filters (red, green and blue). It is the most detailed picture of this object ever taken. The VLT, located in the Atacama Desert in Chile, is the “world’s most advanced optical instrument, and the most productive individual ground-based facility,” according to the ESO, although it will soon lose this crown to the planned European Extremely Large Telescope (E-ELT) due for completion in 2022.