Planetary nebulae are generally faint objects; none are visible to the naked eye. The first planetary nebula discovered was the Dumbbell Nebula in the constellation ...
Planetary nebulae are the cloudy remnants of smaller stars that have shed their outer layers of gas, but haven't exploded into supernovas.
A planetary nebula forms when a star can no longer support itself by fusion reactions in its center. ... Here are several rather unusal examples of planetary nebulae.
Planetary Nebulae are typically small, faint nebulae, found between the stars as comparatively rare objects. Once thought to be strange, odd objects, evidence has ...
Physical and spectral properties of planetary nebulae. Planetary nebulae are typically one light year across and are expanding at a rate of about 20-50 km per second.
Editor's choices for the most educational Astronomy Pictures of the Day about planetary nebulae: APOD: 2005 June 12 - M2 9: Wings of a Butterfly Nebula
What is a planetary nebula? | Cool Cosmos ... William Herschel called these spherical clouds planetary nebulae because they were round like the planets.
Picture Album: Nebulae: Planetary . Results per page:
Planetary nebula are not very bright. None of them are bright enough to see without a telescope. The first one discovered was the Dumbbell Nebula.
A Planetary Nebula Gallery. 10.10.12 . This gallery shows four planetary nebulas from the first systematic survey of such objects in the solar neighborhood made with ...