Resources
Q & A
Glossary
Acronym Guide
Further Reading
Outside the Site
Google Sky
WWT
Facebook
Youtube
Twitter
Flickr
Pinterest
Multimedia, Etc
Images/Illustrations
Animation & Video
Special Features
Chandra Podcasts
Desktop Images
The Big Chandra Picture
Presentations
Handouts
Screen Savers
Audio
Web Shortcuts
Chandra Blog
RSS Feed
Chronicle
Email Newsletter
News & Noteworthy
Image Use Policy
Questions & Answers
Glossary of Terms
Download Guide
Get Adobe Reader
Q&A: Normal Stars, White Dwarf Stars, and Star Clusters

Q:
The term "Planetary Nebula" seems misleading. Why are they called that?

A:
Planetary Nebula Mz 3
Planetary Nebula Mz 3
The definition of the term "planetary nebula" is historically correct, but the term is a misnomer. Some planetary nebulas appeared to look like giant planets, specifically Uranus, when viewed through a small telescope by William Herschel, who coined the term. Astronomy is a very old field of study, so historical artifacts like this are not rare.

Planetary nebulas are really shells of gas cast off by evolved, Sun-like stars. The Sun should experience this phase in a few billion years.

Back | Index | Next