National Aeronautics and Space Administration Logo
Follow this link to skip to the main content NASA Banner
Solar System Exploration
Planets
Comets
   Overview   Read More   Gallery   Education 
Comets:
Color image of comet against a background of stars.
This image of Comet C/2001 Q4 (NEAT) was taken at Kitt Peak National Observatory near Tucson, Ariz. in 2004.

Comets are cosmic snowballs of frozen gases, rock and dust roughly the size of a small town. When a comet's orbit brings it close to the Sun, it heats up and spews dust and gases into a giant glowing head larger than most planets. The dust and gases form a tail that stretches away from the Sun for millions of kilometers.

Featured Mission: Rosetta
Europe's Rosetta mission is on a 10-year mission to explore comet 67P/Churyumov-Gerasimenko. The spacecraft will orbit the comet and study it as it approaches the Sun and deploy a lander to make the first landing on a comet.

Read More About Comets Blue arrow

Just the Facts
Resources
People Spotlight
Mark Hofstadter Mark Hofstadter
"To me, being a scientist means seeing something in nature and wanting to figure out how it works or why it is the way it is." Read More...
Peter Jenniskens - Research Scientist
Dee McLellan - Teacher/Observatory Coordinator
Doug Ellison - Visualization Producer
Headlines
Calendar
1 Feb 2011 - 28 Feb 2011: 
14 Feb 2011: 
22 May 2014: 
Nov 2014 - Dec 2015: 
10 Nov 2014: 
Awards and Recognition   Solar System Exploration Roadmap   Contact Us   Site Map
NASA Official: Kristen Erickson
Outreach Manager: Alice Wessen
Editor: Phil Davis
Science Writer: Samantha Harvey
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: 8 Oct 2010