Subj : Daily APOD Report To : All From : Alan Ianson Date : Fri Oct 16 2020 00:45:01 Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2020 October 16 Planetary Nebula Abell 78 Image Credit & Copyright: Bernhard Hubl Explanation: Planetary nebula Abell 78 stands out in this colorful telescopic skyscape. In fact the colors of the spiky Milky Way stars depend on their surface temperatures, both cooler (yellowish) and hotter (bluish) than the Sun. But Abell 78 shines by the characteristic emission of ionized atoms in the tenuous shroud of material shrugged off from an intensely hot central star. The atoms are ionized, their electrons stripped away, by the central star's energetic but otherwise invisible ultraviolet light. The visible blue-green glow of loops and filaments in the nebula's central region corresponds to emission from doubly ionized oxygen atoms, surrounded by strong red emission from ionized hydrogen. Some 5,000 light-years distant toward the constellation Cygnus, Abell 78 is about three light-years across. A planetary nebula like Abell 78 represents a very brief final phase in stellar evolution that our own Sun will experience ... in about 5 billion years. Tomorrow's picture: light-weekend __________________________________________________________________ Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) NASA Official: Phillip Newman Specific rights apply. NASA Web Privacy Policy and Important Notices A service of: ASD at NASA / GSFC & Michigan Tech. U. --- MBSE BBS v1.0.7.18 (GNU/Linux-x86_64) * Origin: The Rusty MailBox - Penticton, BC Canada (1:153/757) .