NOUN
- a nebula that was once thought to be a star with its planets but is now thought to be a very hot star surrounded by an expanding envelope of ionized gases that emit a fluorescent glow because of intense radiation from the star
How To Use planetary nebula In A Sentence
- The reason why most planetary nebulae are not spherical is not well understood.
- I know that a planetary nebula is different than a hydrogen cloud. About: The Progressive Diminishment of Man
- NGC 2818 is a beautiful planetary nebula, the gaseous shroud of a dying sun - like star.
- The "puffing" from the AGB star converting into the PNN Planetary Nebula Nucleus is not like a switch that is instantly turned off, but is likely an intermittent affair. Red Giant Brightness Variations Still Mysterious | Universe Today
- The average radial velocity of 47 planetary nebulae is about 45 km. per second; and, if the motions of the planetaries are somewhat at random, their average velocities in space are twice as great, or 90 km. per second. Popular Science Monthly Oct, Nov, Dec, 1915 — Volume 86
- The nebula is clearly a planetary nebula, and the gas seen above composed the outer layers of a sun-like star only 10,000 years ago. SETI Institute: Life at the SETI Institute: Paul Estrada -- From Dust to Planets
- In keeping with astronomical tradition, the new planetary nebula will probably be named after its lead discoverer.
- Sure enough, there was a huge shell of clumpy, hole-riddled gas that looked like a nearly dissipated planetary nebula.
- "Planetary nebulae are shells of gas ejected by dying stars, " Kastner explains.
- We note that even if magnetohydrodynamic forces are not the main driving mechanism for the Source I wind, magnetic forces may still play a key role in shaping the outflow, similar to what has been proposed for planetary nebulae e.g., Blackman 2008 and references therein. New Movie Reveals Birth of Super-Suns | Universe Today
