National Aeronautics and Space Administration Logo
Follow this link to skip to the main content NASA Banner
Solar System Exploration
Facebook Twitter YouTube Facebook Twitter YouTube Flickr iTunes
Follow Us
Dictionary Lookup
 
Can't find it? Don't understand it? Ask us.
Q
ultraviolet

Light that is so blue humans cannot see it. A band of the electromagnetic spectrum between the visible and the X-ray. Photons of ultraviolet light are more energetic than photons of visible light.

umbra

The dark central region of a sunspot.

undae

Dunes (literally 'waves').

Uranus
Uranus is the seventh planet from the sun. It is the third largest planet in our solar system. Uranus is named for the Roman god who is father of the Titans.
HREF="../planets/profile.cfm?Object=Uranus">More on Uranus >>

Uranus and moons Miranda and Ariel
Awards and Recognition   Solar System Exploration Roadmap   Contact Us   Site Map   Print This Page
NASA Official: Kristen Erickson
Advisory: Dr. James Green, Director of Planetary Science
Outreach Manager: Alice Wessen
Curator/Editor: Phil Davis
Science Writer: Autumn Burdick
Producer: Greg Baerg
Webmaster: David Martin
> NASA Science Mission Directorate
> Budgets, Strategic Plans and Accountability Reports
> Equal Employment Opportunity Data
   Posted Pursuant to the No Fear Act
> Information-Dissemination Policies and Inventories
> Freedom of Information Act
> Privacy Policy & Important Notices
> Inspector General Hotline
> Office of the Inspector General
> NASA Communications Policy
> USA.gov
> ExpectMore.gov
> NASA Advisory Council
> Open Government at NASA
Last Updated: 25 Oct 2013