Jupiter’s Ghost

Bruce Bal­ick and Jason Alexan­der (Uni­ver­sity of Wash­ing­ton), Arsen Hajian (U.S. Naval Obser­va­tory), Yer­vant Terz­ian (Cor­nell Uni­ver­sity ), , Mario Perinotto (Uni­ver­sity of Flo­rence), Patrizio Patri­archi (Arcetri Obser­va­tory) and NASA/ESA

For unknown, curi­ous rea­sons, early observers of NGC 3242 thought it resem­bled the planet Jupiter, giv­ing it the name the Ghost of Jupiter. Oth­ers called it the Eye Neb­ula. Explore this image of the plan­e­tary neb­ula. NASA’s Hub­ble Space Tele­scope shows great detail of the cen­tral ring and the shoot­ing red gas of bipo­lar flow.

Plan­e­tary neb­ula form when Sun-like stars reach the end of their lives. After run­ning out of hydro­gen fuel, the cen­tral star grows to a huge red giant. Later, the star sheds its outer lay­ers, cre­at­ing a bub­ble in space. The inner ring seems to have snow­plowed into the sur­round­ing quiet neb­ula. Intense, ultra­vi­o­let radi­a­tion from the core star excites, or ion­izes, the shells of gas, caus­ing them to glow. Like neon signs, dif­fer­ent gases within the neb­ula glow with dif­fer­ent col­ors. Even­tu­ally the small hot core left behind will become a white dwarf. The core star has a tem­per­a­ture equal to about 1,000 Suns or about 90,000 Centi­grade (161,000 Fahren­heit). Our Sun will not reach this stage in its life for another 4 bil­lion years.

NGC 3242 is found about 1,400 light-years from Earth toward the con­stel­la­tion Hydra, the Snake. William Her­schel first dis­cov­ered the neb­ula in 1785.