NASA – National Aeronautics and Space Administration
Download Image
The Formation of Titan’s Haze
This illustration shows the various steps that lead to the formation of the aerosols that make up the haze on Titan, Saturn’s largest moon.
When sunlight or highly energetic particles from Saturn’s magnetosphere hit the layers of Titan’s atmosphere above about 600 miles (1,000 kilometers), the nitrogen and methane molecules there are broken up. This results in the formation of massive positive ions and electrons, which trigger a chain of chemical reactions that produce a variety of hydrocarbons. Many of these hydrocarbons have been detected in Titan’s atmosphere, including polycyclic aromatic hydrocarbons (PAHs), which are large carbon-based molecules that form from the aggregation of smaller hydrocarbons. Some of the PAHs detected in the atmosphere of Titan also contain nitrogen atoms.
PAHs are the first step in a sequence of increasingly larger compounds. Models show how PAHs can coagulate and form large aggregates, which tend to sink, due to their greater weight, into the lower atmospheric layers. The higher densities in Titan’s lower atmosphere favor the further growth of these large conglomerates of atoms and molecules. These reactions eventually lead to the production of carbon-based aerosols, large aggregates of atoms and molecules that are found in the lower layers of the haze that enshrouds Titan, well below about 300 miles (500 kilometers).
This illustration shows the various steps that lead to the formation of the aerosols that make up the haze on Titan, Saturn’s largest moon. When sunlight or highly energetic particles from Saturn’s magnetosphere hit the layers of Titan’s atmosphere above about 600 miles (1,000 kilometers), the nitrogen and methane molecules there are broken up. This results in the formation of massive positive ions and electrons, which trigger a chain of chemical reactions that produce a variety of hydrocarbons. Many of these hydrocarbons have been detected in Titan’s atmosphere, including polycyclic aromatic hydrocarbons (PAHs), which are large carbon-based molecules that form from the aggregation of smaller hydrocarbons. Some of the PAHs detected in the atmosphere of Titan also contain nitrogen atoms. PAHs are the first step in a sequence of increasingly larger compounds. Models show how PAHs can coagulate and form large aggregates, which tend to sink, due to their greater weight, into the lower atmospheric layers. The higher densities in Titan’s lower atmosphere favor the further growth of these large conglomerates of atoms and molecules. These reactions eventually lead to the production of carbon-based aerosols, large aggregates of atoms and molecules that are found in the lower layers of the haze that enshrouds Titan, well below about 300 miles (500 kilometers). Image credit: ESA/ATG medialab
Titan haze
Learn how our members and community are changing the worlds.
Our citizen-funded spacecraft successfully demonstrated solar sailing for CubeSats.
Space Topics
- Planets & Other Worlds
- Space Missions
- Night Sky
- Space Policy
- For Kids
Learn
- Articles
- Planetary Radio
- Space Images
- Videos
- Courses
The Planetary Report
The Year in Pictures
The December Solstice 2020 edition of our member magazine showcases the year’s best images.
Get Involved
Volunteer as a space advocate.
Join fellow space enthusiasts in advancing space science and exploration.
Get updates and weekly tools to learn, share, and advocate for space exploration.
- Renew Membership
- Support A Project
- Shop to Support
- Travel
- Other Ways to Give
The Planetary Fund
Accelerate progress in our three core enterprises — Explore Worlds, Find Life, and Defend Earth. You can support the entire fund, or designate a core enterprise of your choice.
About Us
- Overview
- Strategic Framework
- News & Press
- Careers
- Contact Us
- Our Story
The Planetary Society
Our Vision
Know the cosmos and our place within it.
Our Mission
Empowering the world’s citizens to advance space science and exploration.
Titan’s haze